In the end it was a very difficult decision and went with the safe option (but could have ended up with either). Part of me wished I had ordered the M135i but I know that I will be just as pleased with the GTi.
Has anyone else been torn with making such a difficult decision? What swung it for you?
I'm trying to make that decision at the moment, coming from a 123d.
I think the M135i is more of a golf R rival and is good value, but shame it has such a small fuel tank and crap range.
The 125i is more equivalent to the golf GTI, at least as far as price and power. Less standard kit though.
The 125d is a golf gtd rival. It's quite a bit more powerful, but more expensive.