I'm jealous.... the highest I've ever flown my leaky-E model was 27...
In 1987 I took a leaky E-model to FL310 off the coast of France during one of their (many) ATC strikes. Talk about hanging on the props! But it had to be done to get back to Moldyhole.
Two years later coming out of Stockholm near empty, we were comfortably at FL 290, and the engineer said we could 'prolly make 330. Asked the controller, and we were DENIED!!! Don't need no stinking prop-trash garbaging up the central european airspace.
Drats.