I have one and used it quite a lot (a couple of times a week at least) all through last year's hosepipe ban, for washing bikes and watering the garden.
It's worked fine except it became increasingly difficult to get a sealed connection between the hose and the unit. On inspection the little rubber ring on the hose connector had become loose and floppy. I contacted Nomad and they sent me a couple of spares, and their advice is to grease those connections. They were responsive and helpful, it was within the warranty period.
The pressure is just right for washing bikes with a brush.
I agree the warranty is a little short. I've no idea if other units would be any better or worse. The Nomad has worked will aside from the rubber ring issue.