big thumb up for solarshower ;D ;D ;D
i trip in may and have alway's just jumped in the lake when i got so i couldn't stand myself any longer :P :P!
if you've never been in the BW or Q in spring then think of pouring a bucket  of ice water over your head and trying to lather up and pouring another bucket to rinse off :o :o!
it maybe "macho" but it's damn sure not enjoyable!!
last year i brought a solar shower for the first time.
it's the model that holds about 21/2 gallons, weighs about 11 oz.
i found that every couple of day's the weather usually co-operated and gave me a nice sunny travel day.
i would fill it up before leaving camp for the day, or after the last portage.
i would lay it in over a pack so the sun could hit it as i paddled.
you know how much sun you get off water and kevlar or aluminium as we've all had  paddler's sunburn, one time or the other :-[ :-[.
when i get to camp, i lay it on a rock with the most sun exposure and set up tarp and tent, cut firewood and when that's all done, i will treat myself to a nice hot shower and change of clothes ;D ;D!
after a couple of day's or more of sweat,bug dope and campfire smoke, it's nice to feel half-way clean!!
the size i have is plenty for one person to take a long shower but might be to small for couple??
i think rather than go to 5 gal size, you might be better off with two smaller one's as i think they would heat faster??
plus, 5 gals is over 35 lbs, so it's not the easiest to hang??
of course if you use the pulley system for your food pack, you can use it for hanging your shower to what ever height you need :D.
could i get along without it?, sure i could but i could say the same about drinks around the camp fire,good food or extra fishing tackle!!!
my motto is, i don't might working my butt off paddling  and portaging, but i'm going to eat well and at the  end of the day and enjoy a cocktail and sleep without smelling like a old sweat sock :P :P :P.
IMO, it's worth the extra weight involved ;) ;).