I transitioned from a C-172 to a legacy about 6 years ago.  At the time I only had time in a C-172, with about 700 hours in that plane.  I had not time in complex aircraft.   

I took 8 hours of training with HPAT.   This type of training was critical. If I had not had that training I feel that I would gave been a statistic.  I have about 350 hours in N272AG.   I feel very comfortable in the plane now.  It was about one year before I started feeling comfortable in the plane.   I had nobody in my area (Nashville, TN) to help me with my transition.    I'm not endorsing this as viable transition, just FYI.   As a matter of fact I would discourage such a transition.   

Abe Gaskins