At the moment I'm running the Bluespark box, cost around 250 quid. Its cheap and effective and easy to install and uninstall as you wish. I'm getting something like ~210hp using various measuring apps on my car, and seat of the pants feel is definitely improved. At the moment I'm getting about 44 around town and 54+ on long motorway runs with the box set on 'high' map /with 75% effect. Debating this with the Bluespark guys they said it is not unknown for the max boost settings to be the most economical. They don't seem to do as good a job with the 136hp engine which is a surprise as it should be same hardware, but I would have thought that your car 'post tune' should return similar mpg to mine. And of course it will have more torque than a tuned 2 litre petrol, so its not all bad being on the 'dark' side 
Having said all that, if you really want to get a decent non reversible remap then AHM has to be the way to go. More than twice the price but that will take you to 240hp and they will blank your EGR, which may also help your performance issues as well. It isn't cheap but I may well go that route in the new year and sell the Bluespark box to someone else who wants a cheap reversible option for warranty or other reasons.
Having said all that, if you really want to get a decent non reversible remap then AHM has to be the way to go. More than twice the price but that will take you to 240hp and they will blank your EGR, which may also help your performance issues as well. It isn't cheap but I may well go that route in the new year and sell the Bluespark box to someone else who wants a cheap reversible option for warranty or other reasons.
