Thanks for all the appreciation so far.
Although local (read flat) trails have helped me 'bed in' the niggles from the build, I needed to get out on the big stuff, so this afternoon, was spent on every inch of gisburn forest.
5 mins in and I got a puncture from a thorn, so repaired that and then really it was faultless throughout the rest.
New sintered pads were bedding in the new discs nicely. Takes a while for them to warm up, but then they're fine. They were getting sharper and more responsive as the afternoon went on.
As the trail was very dry, it made for a very fast ride, and those tyres aren't really best for dry hardpack and rock, so a little scary at times.. I had a great time with her and really loved the feel and feedback from the bike. The trail has some uncomfortable sections where the big sharp rocks are above the quarry, and this bike really isn't suited to that. However, on the old worn, smoother singletrack, this was uncatchable - a combination of knowing the trail like I built it, and a bike that felt more alive the harder you pushed it.
The M953 XTR is amazing when compared to previous Shimano offerings. It performs so smoothly, quickly and accurately v's the M900 stuff.
I love all my bikes, but this one is special. In fact I'm besotted!
Here's a few photos just to update the thread.
The toadstool was real and bloody massive!