I've just used T P Matrix for the first time to service two projectors. Excellent service and reasonable prices.
They understand schools, suggested doing the work over Easter, and returned the units promptly on the first day of term.
The two projectors (Sanyo and Panasonic) came back as good as new. The purple blotches and darkness in the image were gone.
They are Sanyo approved, but they'll do most makes.
Would definitely recommend and use again.