There are a number of threads re: the MH Golden lounge in KUL. On your MH flight I believe you'll be allowed access to the business class side, where you'll find big, modern, clean bathrooms with great showers, good food, and massage chairs.

The Plaza Premium lounge, nearby, is what KL uses, and while it is not as opulent and feature-packed as the MH lounge, it is much nicer than anything you'll find in the US. Food there is also good (as in real hot food) but again not MH quality. I seem to recall showers there as well, but I think they were small and basic. I didn't use them.

Tips: rumor has it that once inside the MH lounge you can pass from the J to F sides right behind the backs of the attendants. Not that you should do that, of course. Also, the Plaza Premium lounge has two "sides" as well - one for Joe Sixpack who can just buy an entry for something like $15, and the other (smaller, nicer) one that is reserved for premium and elite pax. Make sure you get the right entry, or you'll be underwhelmed.

Edited to add: here is a link to info on the Plaza Premium lounge: http://www.plaza-ppl.com/kl_en/lounge.php
And here to the MH lounge: http://hq.malaysiaairlines.com/mys/e...en_lounges.asp