Hey Breen,
I'm going to a DI system as well. I've bought mine but have not recieved it yet (ordered it just before new Years). So, Obviously I have not much to say or offer besides the fact that I think this will be the wave of the future. I bought my unit from a guy named Shawn Gavin, his company is
Reach Higher Ground-Home Page He seemed very knowledgable and honest but that is far as I will go - check him out for yourself (I don't know him well enough to make him my recommendation).
At the very least you should get a TDS (total desolved solids) meter to evaluate your water purification needs. If you have high solids over 150 parts per million you will need more equipment - more upfront money.
Hope this helps, Tim
Hope this helps,