Power supply no, but ND5 XS2 > DC1 > nDAC is a known alternative to upgrading to the NDX2. It even has its own thread, perhaps have a look here:
Wow, what a special place to live! Don’t worry about the Exact, in my experience it’s pretty sturdy and you’ll hear when it starts to deteriorate, or your dealer could inspect it for you.
@daddycool it is indeed a great place to live. My husband has the aesthetic sense. We discussed better speakers which would interfere with our view. He ruled that out. Also he does not want the equipment racks to be near the speakers which would have reduced speaker cable length but messed up the view. Since he hardly ever objects to stereo expenditures I need to respect his aesthetic sensibility.
Just sit back relax and enjoy your music
I used a pair of small Kudos speakers for quite a few years, and like you I really didn’t want tall boxes that dominated the room. I knew they were the weakest part of my system after upgrading the source and amp, but I realised that better nearly always meant bigger, especially if you want floorstanders with decent bass extansion. I eventually discovered Shahinian Acoustics, who happen to be located a stone’s throw from you in Long Island. Their polydirectional loudspeaker designs are unconventional, and use cabinets that are not nearly as tall as a typical floorstanding speaker. So I now have a pair of Shahinian Arcs, which are not particularly small in volume, but are only 27 inches tall.
The downside is that they do need a bit of power to perform at their best, so they might require something a little more powerful than your Supernait.
Shahinian are indeed special, didn’t know they’re from Long Island. Really liked the Super Elfs and the Compass 2, which work fine with a Nait 2.
Have not heard the Arcs but when @ChrisSU recommends them with the caveat of needing more power even than a SN3, buying local has its charm! (Grado in Brooklyn should be close by as well).
Alternatively Neat Iota Alpha / Motive SX2 and Rega Aya for British style, or for European flavour stylish small floorstanders Piega Ace and Davone Moxie .
But this thread was about not having to upgrade! 
Heave a sigh of relief, and revel in the fact that the only new hifi gear you’ll ever need to fund is replacements in the event of failure (mainly mechanical things like CD players) or in the case of online streaming (as opposed to streaming from your own store) in the event of required software developments proving incapable of being retrofitted.
N.B. There is a contradiction in your opening post, your dealer telling you don’t need to upgrade but in effect also advising that you might do better with a change of speakers… (symantics of course, need vs potential to sound better).
A certain phrase springs to mind…… where’s the catch 
@Innocent_Bystander the dealer said that if I really felt compelled to upgrade, the system could support much better than the Spendor A4. However better would mean taller which my husband did not want b/c it would compromise our view. I need to respect his aesthetic sense. Besides which, we like how the A4 speakers sound. If I felt a lack, I could have afforded making a significant speaker change.
There was also the question of speaker/room interaction. The room’s construction materials were such that many speakers perform poorly in our living room. The A4 speakers performed without issues. Given all things considered, we decided not to chance changing speakers.
Not really wanting to spend Your money, but I’d given up on what I think may be the best for my current system (282/250dr). But today noticed 2 pairs of kudos titan 606 for sale. Naturally both are on the west coast, but they would “fit” similarly to the spendors . Currently, there is no U.S. distributor as far as I know. Don’t know if they would be of interest. Also fwiw, I pulled the trigger today on an alluxity int. 1 mk11. Reduced box count but same location (rack) so not sure how much I’m “saving”.
Hi @Jaybar less than 6 months is not a lot of time to own a naim system and it is entirely possible that the sound will further improve without any changes at all.
My advice is to carry on enjoying your music collection and the view.
Has anyone suggested building a 2nd system? Perhaps something luxurious for the kitchen or bedroom?
This is kind of where I’m at at the moment as I’m satisfied with my living room set up. Thinking about ways I can annoy my wife even more 
@mbear one system is enough for us.
I have a Uniti Nova with Focal Sopra no1 in one side of my living room. Other side of my living room I have a Naim Muso. Really nice, it makes me enjoy the music without having to adjust volumes when I move into another part of the room. The rest of the house I have a couple of Muso’s so the music gently fills the house.
I do have a Rega P3 next to the Uniti.
Tidal is my streaming service.
Any suggestions or advice for an even better experience?
two words: Nakamichi Dragon
Personally, I spend the money saved upgradeitus-ing on live music and CDs, listen to my music and enjoy stuff I’ve accrued in over 50 years. I’m listening to a new to me Mingus CD right now grinning like a loon. This is good!
Your dealer sounds wise and honest. Buy him a nice bottle wine and enjoy your music.
Thats a half year only in ownership.
Bit short time me thinks
I’d say the CD player could be better.
I do expect you have sorted mains, cables, racks etc…?
The dealer clearly failed to dissuade their customer from the purchase of an ndx2 and xpsdr after barely 5 months of owning the nd5xs2.
For those who keep taking jabs at me for purchasing, there were sound reasons. I purchase new and not used. My dealer was able to secure a new XPSdr for a great price. Had I waited it would not be available. Regarding the NDX2, this was something I should have purchased with the SN3
However, at the time, we had never done streaming. It was only when we decided to hard-wire to the router that streaming became viable. Where the stereo is, is also a WiFi dead zone, so until now, streaming was never an option. Even with running Ethernet, it was by no means a certainty. Moreover, we did not know if we would even like streaming. The most important factor in deciding on the NDX2 to replace the ND5XS2, was my dealer’s generous trade in offer. Lastly, had the NDX2 become discontinued, the next step up for a Naim streamer would be more than I wanted to spend.
Your purchase was exactly the right decision! I also went from brand new ND5XS2 and XS3 to brand new NDX2/SN3 but I didn’t wait 6 months!
While I never added a PS in my 5 years of NDX2/SN3 ownership, I knew that it would have made a significant upgrade but funds at the time and other priorities got in the way.
Enjoy your system and take no notice of other opinions.
Second that @Jaybar I’m really happy for you that you had budget and opportunity to make that move as it’s surely a very rewarding one, resulting in an overall system one can enjoy and be proud off.
Myself I would likely have gone left here and there where you went right, but no matter these are the experiences as members of this owners forum we share out of enjoyment of such ownership. After all this, please now simply enjoy your NDX2/XPS-DR with SN3/HC-DR, a classic high-quality system.
When you are ready to tackle your planned turntable upgrade you know where to find us