Keep away from the chip boxes, old technology.
Had a few cars re-mapped with great success. car manufactureres produce an engine configuration that will work in all parts of the world, and as we live in a temperate climate there is plenty of BHP to be gotten across the whole power curve. when you go for a remap you can advise what you want, most boy racer types tune for speed lower down the power curve so they can try and burn you off on the strip (traffic lights on the high street). Some want the tune to give extra power top end of the power curve (think track day cars want this) but most go for the sensible power increase across the whole curve. If you have this type of remap you will find the car a much more enjoyable car to drive, and if driven sensibly changing gear less, thus saving fuel. For me the biggest pro is the instant ooommpphhh i.e. reduced turbo lag, so when cruising it makes for a much better drive and you don't have to change down if you want to accelerate very quickly which is good when in a dodgy situation on the motorway as it gives more options.
If you have it done then it is worthwhile improving the breathing of the car, both air intake and exhaust (free flow) and if its a diesel get rid of the cat as it's just a soot collector and provides resistance to the Turbo.
