Since the 3.X series of RouterOS is the way to go then I upgraded some of my RB532/RB532A boxes with it. I have following issues:
1. 5 GHz channel tables for R52 changed. With 2.9.51 I used the Russian channel set and after upgrade it turned out that 3.7 Russian channel set is different and 2.9.51 units did not see the 3.7 ones. Are the 3.7 channels final or do they change in the future? Also, WinBox country and channel selection will require fixing/improvements as at the current state the country selection does not affect possible channel choices and it will be very annoying to select different channel over and over again just to find one what is correct for that country.
2. WinBox Simple Queue Target Download and Target Upload field names should be swapped around to match their actual behavior elsewhere in Queue list.
3. Time zone selection does not take account of DST. For example Europe/Tallinn does not activate DST.