I checked up on costs, I know the Hilltop is a more leegant and permanant solution with no extra gear to go wrong, but it is expensive compared to the options:
Accelerator Module:- £30, Cheap & Cheerful and probably enough to stop bike running dangerously lean (especially for those with cats removed / cans fitted). Fifteen minutes to fit, easy to remove at service / warranty claim / sale time
Booster Plug:- £100, as above (just not as cheap)
PC3:- £250, Even with a generic map it should be a big improvement on above cheap options, with a custom map it will be even better but this costs about £400+ I guess about an hours work to fit

The PC-V with Autotune I believe is even more expensive than a PC3 + Custom Map.
Hilltop Remap:- @£400, Probably better results than above, but it stays with the bike, so no resale possibility. And some are concerend about warranty etc. although it is claimed the dealer will never know.
I suppose it depends what you want, I would rather not have a valve eat itself / burn out and £30 probably goes a long way to stopping this.
Would I like much smoother running and a fair increase in power and torque through the rev range? Well wouldn't we all, and at £200 I am sure the queue outside Hilltop would be a long one. At £400 for a remap / properly setup Power Commander - No thanks.
So I reckon £30 to richen it up a shade will do until I can get something better without spending 8 - 15 times as much.