I try to do an hour a week (at least) and usually do. I usually do the slow flight, stalls, PFL's and that sort of thing for 30 mins and then do 30 mins of circuits.
Once a month I do the club fly out so I get to do my decent lenght cross countrys then.
During the Isle of man TT races I clock up about 50 hours between the PA32 and AA5-B, all on or close to MTOW. So I really get to play about with fuel loads, weights and balance and flight planning.
This keeps me pretty much on the ball.