In reply to didntcomelast:
I'm was also 32" waist the last time I had Rondos (or perhaps slims) in size M, but to be honest I think I the S would have been a better fit... But this is from like 5 years ago or so, so perhaps they have changed the sizing.
To be fair, the M fitted but felt a tad loose at times (on the waist). They never dropped, but a few times felt close to droppin'