Strange you should say that, Alan!
It seemed Cleantech and Omnipole were much the same a couple of days ago, with others trailing. Now Omni has pulled slightly ahead, but Ionics has stormed up to level with them.
Although I've recommended my favourite supplier to lots of folk, I haven't voted here because I really only have experience of three, or maybe four, and they've just been single purchases apart from the main one.
All the best with the van system - let us know how you get on? I'm going for a vanmount when I upgrade to a bigger van in the new year, and I've been trying to make time to get through to Cleantech when they've got a van in. Partly for nosiness, but mainly to pick Mike's brains, and get ideas of my own once I see what happens on an installation. A low and w - i - d - e tank is definitely on the cards for me. Essentially for stability and lower centre of gravity, but also because I've been told that these tanks are fairly robust and can take quite a load on top of them - so gaining more useable space.
Ooops, sorry Alan - went a bit off topic there!