My lee clothes are made from a pvc/cloth type material with brass eyelets in the corners and along the bottom. They are tied (top and bottom corners) to stainless eyes that are screwed/bolted through the bulkhead either end of the berth. The bottom edge is also tied down to small eyes that run along the length of the bunk.
I race quite a bit and use the lee cloths to keep all the sails and kit on the bunks. When not racing I just untie the top of the lee cloth and fold it under the bunk cushions this makes it quick and easy to set them up when entering for leaving harbour.
Mine were acrylic cloth and were screw down with a batten at the BACK edge of the bunk cushion, then running across the the front edge of the mattress and then up to eye at the deckhead. It had the advantage that you could leave the lee cloth shipped, and still get into the locker hatches under the bunk.
I organised a couple of leecloths, last summer, much like PJ's - except I didn't secure the lower part to a batten. That part of the leecloth was tucked under the bunk mattress at least half-width, and body weight kept it in place. There were three eyelets in the upper edge, secured to solid screw-eyes fitted into the sides of the deck beams. Cords as loops, using rolling hitches, permitted easy tightening and loosening, when getting in and out in the dark.
Personal gear was stored on the out-of-use ( uphill ) bunk quite a lot of the time, again without issue. This worked all the way up the west coast, then on to Iceland and back south, without a problem.
Before acrylic was around leecloths were made out of ordinary canvas and being stored under the sleeper they suffered from mould from the condensation and tended to be rather smelly.
OTOH acrylic leecloths, being waterproof, cause even more condensation when your nose is hard against them ! Especially when 'hotbunking' in hard weather.
If you go the Pyrojames route then make sure you have lots of anti-condensation stuff between the sleeper and the leecloth.
The best I have ever used ( in an offshore cruiser that spent many days at sea in very northern waters) were made out of acrylic ( no mould) but had 4" dia. 'holes' all over that were filled in with netting.
Best of both worlds.
Might be worth it for that one important berth - not worth it for all of them , depends on your pocket.
Yep, my canvas ones do tend to go a bit green. I found a good scrub with dilute bleach solution tends to last a number of seasons and they come up as good as new.