Hi Anthony
The new Pheonix's are reverted back to traditional style i.e. back to waste tank, but it is only a mod required to get it to fresh so should be able to be done. I think the only reason why they changed it back to this spec was because of the acid rinse gumming up due to the heat cycle (rather than dumping it to waste). Cant confirm this but this is what happened to me anyway. It was an easy fix - I just use other alternatives for my acid and problem solved completely.
The water isnt really an issue because I'm recovering it back to fresh and its not dumping lovely fresh water to the waste tank - which means I can get away with this smaller set up. On the occasion I need more water - well its not hard lets face it. I would say the only downside is the waste tank does get a bit more dirtier as there isnt fresh water going in their at the same time, but I dont mind this small sacrifice for the benefit of not using so much water.
It is the perfect machine in my eyes:- small (ish), amazing heat, uses less water, simple to operate. I now have it in a LWB Trafic and have tons of room! Will post pics when they wrap is done.
Like I said earlier the Promount (dont know what they call them now) machines are very very good too (in this range the 25 prob the best) - its a tough choice between the 2 tbh, but I would definately get one or the other if it was me. Way more than enough for domestics and a breeze for schools, churches etc. If your gonna do ships then you need something bigger
Kev
p.s. I've just re-read your post re:
'I've also read some lower end TMs don't maintain high temperatures etc' yes this does happen on some (low powered usually), even on my first heat exchanger it did this. But HM have got this sorted now and it doesnt drop off at all, as they re-designed the new exchangers. Anyway, hope this all helps.