careful with that statement...be a bit more specific, cause the M series Markers are just as bad as the padlocks...I went through 5 brakes and split my M.11s in half after 2 weeks (and this was when I first started doing park). However, the Royal series (Griffon, Jester, Duke, Barron) are pretty good though.
I'd say, look for some Griffons, STH 14s, or even some Deadbolts...or if you are really looking get something good and that will last a long time find some FKS...you might have to spend some money, but they'll last an extremely long time and they'll keep your knees happy.