I've read some threads about people having a hard time getting into some gears. I personally couldn't shift into second gear quickly without there being a grind even with my clutch pedal welded to the floor. I would have to pause for seconds and then it would go into gear.
Took it to BMW, 2nd gear syncro issue diagnosed. Replaced transmission and now it feels amazing. Also got a new clutch with the replaced tranny so its really win win apart from the 2 days of not having my car but not a big deal. People that have similar problems, don't live with it. Go and get that shit replaced.
Also, I've noticed a trend at BMW. They do not fix, they replace. I kind of liked that approach with regards to the transmission because instead of tearing up the tranny, they just throw a brand new (or re manufactured) one and bob's your uncle.