I took a shower at DXB J Lounge yesterday and it was pretty good - a lot better than the temporary "campsite" showers that BA offers in T5 arrivals! God I hate those...!
I do agree on lounge layout though - it did feel rather odd... I guess its because its so big that things don't really fall where you expect... I did find myself walking a loooonng way to get my "issued" glass of water etc. I wonder if they've had problems of people over-hydrating??!
In terms of toilets - I found one available at every opportunity - heck, I even had a copy of an English newspaper in mine so I could "catch up" whilst doing "my bit" to save fuel on the DXB to PVG...