Don't go off the quoted power figures! Look at the actual mods you get for the money. Speak to the companies, and see who offers what you think is the best level of service.

I've not driven the others much, but can confirm that the Mountune kit is fantastic, as I've done over 10K miles and it still makes me smile when I get in it.

If you uprate the cams it's sensible to fit uprated valve springs (not all tuners do this), and while Eibachs will be fine, you really won't go wrong with a set of Bilsteins, they're fantastic. The spacers definitely help too.

Finally, if you're given an exhaust option, definitely don't go for a loud one. A boomy exhaust and the short gearing will make journeys unbearable.