We're seriously thinking of using them
NS Optinum run a very hefty chunk of the ICT for a number of schools round here (I'm based in Rugby) I had a new IWB fitted by them a few months ago, within 2 days of picking up the phone to them and honestly the people they sent were brilliant!
The original board was fitted by a idiot from RM, and installers from NS threw in (for free) a new, better projector mount, and were more then happy to fix the ducting mess: moving network and power points, taking out some nasty looking coax and generally they went above what we expected from them! They even took away the packaging (RM's installers DON'T DO THIS!)
I've just had them in to quote for a new server + move to vanilla + wireless + lots of laptops and it's looking well priced - their support product looks like better value then the product we currently have from RM too.
We've not decided if we're going to switch over from RM yet, but they don't look like a bunch of cowboys.