If you are remotely interested in modifications on a 1, head straight to the 1M where you will be immediately in the driver seat of a vehicle some 135 owners spend thousands (and lots of time) to (in a sense) replicate.
This is coming from a modded 135 owner. NOW, I also enjoy luxury with an eye on price point... go shopping! Pick the one you are most comfortable with for the right price. If the 1M has not been abused in its short use, this is a hands down winner (IMO).
Let the car pick you
