The Boxster looks better with the top down in general. Yours is beastly, low and wide. Proper roadster-ing!
If the top gets wrinkly (which is why, I presume, you don't put it down often), get some of that black cover up crap and just keep applying. The dealership put some on when I bought the car and the top looked great for a few months, including some torrential rain. Not bad, especially if you will be driving infrequently.