Because u have the standard Euro, I'm gonna say go for the BMW cos it seems you like the perks and gadgets of the BMW. if you had a Euro luxury on the other hand I'd definitely keep that! my GF has the 2005 E90 320i (auto), I drive it fairly often, but I find it so sluggish coming out of the Euro! fuel economy isn't heaps better than the euro anyway! she averages 10L/100kms
The Euro just feels like a better all rounder!..... If I were you I'd sell your car, but not for the BMW, for a Euro Luxury