I went for a dyno, before they moved from Pirbright to Guildford and was told my car was 70bhp down, which had me in a bit of a panic, but ok that's not their fault... untill a few days later I had a call inviting me to spend lots of money on this, that and the other to get back the power lost. Unfortunately the car was involved in an accident before I managed to get it put on a dyno somewhere else to clarify. I'm not saying they were lying, I just wouldn't say that chucking a load of aftermarket parts at a car is the right way to resolve an apparent 70bhp loss. I'd rather find the cause and fix it before modifying lots of bits.
I then went in just over a year ago, maybe a bit longer, to enquire about having a hydraulic handbrake fitted to my Z. I was told that it was physically impossible to do and that I'd have to get them to create a twin calliper set up on the rear so that the hydraulic handbrake would have it's own bespoke system. Went somewhere else, and sure enough, I didn't need to pay for twin callipers, they just plumbed it in to the standard 350 braking system and it works like a treat.
Edit: Also, I'd love them to be good, they're literally on my way to work so it would be very convenient