Sounds like you my friend, have a lemon.
That or you are one of those people that believe everything they say on the the internet, your statement about MAJOR
issues with turbos failing is inaccurate, asides from the common wastegate rattle which really doesn't affect your performance in any way bmw turbos are actually pretty reliable and like any other turbos eventually need to be serviced or replaced because believe it or not most turbos out there do need servicing at some point specially if you throw on a jb4 to beat m3s all day/Not done with sarcasm.
Fuel pump issues, sure they are common which is why BMW addressed this and will replace them for free every time with no cost to you and likely a loaner vehicle which then again it implies no trouble to you up unto 120k.
Water pumps just in like any other car hit the shitter after a certain period of time, and with am extended warranty that will cost you upwards of $1400 you can have that covered as well as many other things that will break after time just like any other car (i.e starters, alternators etc etc) so believe it or not even BMW has come up with a water pump that lasts forever or even more so a car that something doesn't break on every so often!/End of Sarcasm.
So if you are one of those people who expects to give a car its required maintenance and then some(if you beat on it here and there) i say go for it, a 335 is such an upgrade in so many aspects and i think maybe 1 in 10 people out there regret doing it and that probably is because their car is a lemon, not well maintained or constantly abused. You'll never look back, i promise and if you're anything like me you'll make your wife/gf buy one too