Anyone any experience with Qualitone Avail?

My audi is recommended i get a second hearing aid and he is pushing a qualitone Avail 1200. actually he is recommending that i buy 2 and get rid of the qualitone ha that i presently have in my left ear.
Has anyone any experience of these?
The qualitone i have is mid range and not great - is it possible to wear 2 different hearing aids?
I was hoping to buy a top range aid for my right ear and keep the mid range aid in my left year for cost reasons. Would this work?

any comments would be appreciated. Its hard to know what to do and any advice you get is from sales men which doesn’t help.