UKC

Anyone used any of the line. 

Thinking about the 5l one for longer trainibg runs/ as short trail races where equipment is required to be carried . Current 35l omm is probably overkill...

Obvs much cheaper than Solomon. And more expensive than decathlon. Does 5 l seem about right for what I want to do? 

Not used the Grivel ones, but they do look good.

If it assists your decision making, I opted for the Ultimate Direction AK3 which is about 11L.  I use this for mountain ultra races, and longer training runs.

With this capacity I can carry the compulsory kit for events such as the UTLD 50/100 which includes; waterproof jacket, waterproof trousers, full length spare top and bottoms, spare food, map, compass, 1 litre of water, first aid kit (I always carry more than the minimum), survival bag/blanket, cup, hat, gloves, buff, mobile phone and head torch with spare batteries.  

I find  have plenty if space for an extra layer and a few extra bits like hat, spare gloves, body glide, suncream, sunglasses, gels and a couple of bars, etc.

For shorter races where the kit list is a bit smaller, a well packed 5 litre sack/vest should accommodate what you need. I tried the bum bag approach and could get my kit in for shorter hill runs.  I just didn't like the method of carry.

Thanks Kevin

No one else seems to have used or reviewed one in English.  Ive ordered one and can report back if people are interested.