Well, I have been flying only 2.5 yrs. I bought a Beech Sierra to finish my private license in and flew until May. They are a 200 hp complex aircraft. The cabin is wider than a Bonanza and has 2 front doors. I have around 520 hrs ( 450 in the Sierra, 55 in the 231 now) total time.
The 1 door is taking some getting use to (after you have had 2), more leg room in the rear seats for the wife and kids but a little more narrow. They stability and control feels are amazing. It is the most stable plane I have flown. Speed is, well its a turbo Mooney. I fly from Nashville, Tn to Oklahoma regularly and it cut an hour off that trip each way. Don Maxwell has done the annuals therefore it is in great shape with all the bells. Im finishing my IFR and except slowing the thing down it is by far a better IFR platform. I have put 55 hrs on it in 6 weeks and I am enjoying it. I would recomend the K model if you take trips etc. If only local flying I might would go to the J model. My 2 cents worth.