update:
Went to collect the car yesterday, took her for a drive with Martyn Jeffries to make sure all was ok. Found a couple of clitches with the ecu software which need to be addressed so car is still at the garage.
As for driveability, yes it is more laggy than the 20g previously fitted but i knew it would be, but when it does spool up it holds 1.5bar all the way to the redline with no let off.
The brakes are awesome, bearing in mind they have not bedded in yet! Suspension is firm, but still comfortable.
Cannot comment much more as we retunred to the garage not long after starting the drive so they can start working on ironing out the glitches.
As this is the 1st Simtec ecu for the newage, I was prepared for them to spend some time with R&D on my car, a little dissapointed, but it will be worth it in the end.