Very interested to see what you have mentioned about your wonder wand, as I also took delivery of my mytee on 21st Dec and upgraded the wand, and have used it on a few jobs already. However, I also noticed that the carpet seems to be wetter than a conventional wand, I wonder if it has anything to do with the roller, I am going to take mine off, and see if this helps.
If any of your guys using the WW have any tips on use, I for one would appreciate your input.
With regards to the heat exchangers, the machine is far to new to comment at the moment, I will have to run a few tests over the next couple of weeks.
Regards
Paul