It comes stock with 134kW, with an overboost to 149kW (for 20 seconds when you jam on the accelerator, resetting every time you take the foot off, so pretty much always). Most of the OTT tunes bump it up to around 160kW (including the Mountune). I had a Bluefin tune (162kW claimed), Mountune short-shift kit, and a CPE engine mount. The factory tyres are RE050As so only 'OK' for grip, and not great in the cold (but still better than the Dunlop Sport Maxx tyres on the WRX: what were you thinking Subaru?) I was looking at the Quaife LSD, but soon came to realise that the two-door just wasn't family friendly (moment of realisation came a few months ago when I went to pick up some KEF floorstanders and had to use the wife's Honda Jazz because they wouldn't fit in my car. The embarrassment). I could see it wouldn't be a long-term ownership.
I tried the updated Focus ST as well, but the FWD put me off, as did the problems I've seen with the 2.0 ecoboost (the 1.6 is totally solid in comparison, with people getting 400HP with totally stock internals). The WRX is a manual Premium. It's way more practical, much faster, but less goofy fun (brakes and gearbox are a big step down from the Fiesta, but I'll work on those. Not much I can do about the lightness and go-kart factor: WRX is the same basic size and weight as my old Legacy). I only have 250 km on it ATM, so hopefully shifting will smooth itself out a bit over the next few months.