I bought my son one for his birthday last August and it's been very good, I liked the idea of charging individual cells rather than a pack. This way it lets you know how much has gone into each individual cell in mah's, enabling you to see which one (s) may be dragging your pack down. It gives you the voltage and temperature for each cell and cuts them off seperately, thus preventing cooking a cell while the rest of the pack is still charging. By charging a pack you could have a cell with a very high temperature and not notice as the whole pack hasn't reached the cut off.
He can do his 6 cell side by sides & 3 x3 saddle packs in the internal tray and at the end of charging it will give you a match percentage for the whole pack. You can also charge at the same time on the external ( pack only no individual cell monitoring) or run a motor in from it.
Simply one button click & spin set up which takes a little getting used to but once you have it's easy. I'm just about to plug his into the computer and download the latest software update for it.
Expensive if you buy from the U.K., which I did as at least if something does go wrong you've a local point of contact, but IMHO worth every penny.