I’ve been running 606 for the last year with 252/300DR and KS-1 speaker cable and they are magnificent.
Mine are 30cm from wall but I’ve had them as close as 15cm too. I have experimented with toe in and settled on very slight (<10 degrees each side)
Mine took about 150 hours to run in. Kudos also recommend volume when running in too👍
You’ll love yours. A great companion with Naim. I normally listen with grilles on but have experimented with off too.
A quick phone snap. Apologies for quality. Will get around to sorting those cables when the room is decorated…
Oh. And just 
Mine are 26cm (back panel) from rear wall and 2.0m apart (centre to centre), with no toe in.
I listen, from a distance of 2.5m, with grills on.
My understanding is they were designed to be listened to with grills on, though that may be apocryphal.
To my eyes they look better with grills on. So have never experimented with it - it also makes them less interesting to small children.
Wonderful speakers.
I’ve started 25cm from back wall with no toe in, 2m apart and I’m 3m away. Agree they look better with grilles but daren’t with my cats. They do indeed sound wonderful.
The Kudos advice is, after initial placement, to run them for 100hrs and then experiment with positioning.
I found mine only needed a slight tweak from my dealers initial placement - moved them slightly closer to rear wall, slightly closer together, and removed the slight toe in the dealer set.
Oh, and our cat shows not the slightest interest in them.
Reaction so far versus the ATC SCM11.
The SCM11 haven’t been put to shame, they’re very fine speakers.
The Titan’s fill the room. Effortlessly. Much bigger and deeper soundstage.
The occasional treble harshness I got with the SCM11 has gone. Trebles are more detailed but sweeter at the same time.
The SCM11 sounded a bit ‘shouty’ at higher volumes (sorry best word I can think of to describe it). The Titan’s just grow without sounding pushed. I think I could listen to these very loud!
More detail, more of everything.
Very happy so far 
I think I’ll change the speaker cable from Witch Hat N2 to Kudos KS-1. It’s well reviewed on here and the price and diameter in particular is a huge bonus. Based on the experience of @Polarbear I’ll speak to Cymbiosis about terminating them for me with Naim plugs for the amp end and Kudos plugs at the speaker end.
Its worth it Stu and Peter certainly knows which termination plugs not to use.
Enjoy your 606’s, I am very happy with my 808’s, they will be here for a very long time. 
These really are wonderfully simple to position and tune. Started at 20cm from back wall, a bit boomy and bass heavy. Pulled forward a cm at a time and the bass was better balanced each time. Settled at 23cm for a very full rich controlled bass. Might come forward another cm or two but that will be it. Had them at 30cm last night but the bass is more to my liking now. They do go very low!
Firing dead ahead, 2m apart, as per Kudos’s recommendation. Nice to have them near the wall and not imposing themselves too much into the room.
Mines are at 35 from the back wall now and they sound lovely and rounded. Pulled them out a bit more for aesthetic purposes, all good.
I’ve also now got them firing straight forward, no toe in.
Enjoy.
I originally had to pull them out a bit more from the wall to accommodate a change from 250DR to 300DR.
Sweet!
Just now there is a novelty factor in having all that bass on tap, but yeah in time I’ll probably end up pulling them out a bit for a more natural presentation
Def opened up the mids a touch. Worth a try but not until well run in.
I have the same issue, they are off as the cat saw them as a scratching post! If it was not for the cat I’d probably have them on, though they are not too unpleasing to the eye off.
My oak 606’s are driven by a NAC282/NAP250DR/HICAPDR. This combination amply drives the speaker in terms of volume and control. I use Kudos KS-1 cable.
The oak and black together look very nice indeed
@buster I had put the grilles on but think I’ll take them off now!
Out of interest, are any Kudos 606 (or 505) owners satisfactorily using them positioned very close to a wall (ie. as close as SBLs and SL2s are normally positioned)?
edit: Andy’s look pretty close to me in the pic above
