APR maps are one of the best but do pay the extra for a custom rolling road tune, you’ll end up with a smoother, quieter engine with better mpg and power. They should quote an all in price for all the work, which includes saving your original map should you need to go back to it and checking for faults before a new map is installed. If warning lights come up then something is wrong elsewhere on the car. If the clutch is well worn this will limit power and torque of the end result, the tuner should advise you if this is the case.
Before you go do a basic service changing oil and all the filters.
Gaz78 says his remap was £300 which is a bargain, it would be £100 more down here in the Balmy South so well worth considering.