I wonder if something has changed and someone has found a sweet spot/right technique when tuning these?
I looked when I first got my car and there weren't many options really, of those few some quoted =< 5bhp but better acceleration and economy and others were just plug and play units that trick the drive by wire accelerator switch to go 'WOT' when only half pressed etc.
All stuff that would give the illusion of a bigger improvement but not really doing a lot...
However I recently had a quote for similar power and torque increase from a company that previously didn't map the 1.8
Without a before an after graph to prove I wouldn't be parting with any cash. I don't actually know what the base 1.8 really puts out, it's fairly common knowledge the 140bhp 2.2 dervs pump out closer to 150 standard with a shed more torque.
not sure if the petrol lumps are a under quoted a bit too. Trouble is as these cannot be or are hard to map not many people bother dyno'ing these.
Perhaps be a guinea pig for us and see if they will offer dyno runs to prove?
They could recoup the losses very quickly from the 1.8 owners on here who would be interested.
Those increased figures on an N/A car are an absolute bargain! especially when exhaust options are so limited and likely to cost £400 minimum for catback only.