Lomo & Ortlieb Rucksacks Float tests

Lomo were kind enough to send me a 60L rucksack to trial for swim camping. Took it for a float test last weekend along with my own Ortlieb Xtremer rucksack. Both worked really well with the camping gear inside, floated no bother, no leaks (have kit doubled bagged inside (I use sea to summit big river bags). Had 3 tow float leashes looped together, leaving the rucksack far enough back from my feet to hardly notice it was there. Will see if I can come up with something stronger..Suggestions anyone?...Main issue is that we swimmers have to take clothes in the rucksack to get into after swimming, they take up a bit of space in the bag...Looking forward to Donna and myself having mini swim breaks to some of our offshore islands...anyone else fancy doing something like this? This is for leisure and enjoyment....