Did you ask them why they hate it? You haven't lived with it and depended on it. You've only tried it. Typically people who don't like their atomizer
tank systems of any kind have issues with leaking or burning taste due to not enough liquid wicking to the coil, or the typical atomizer problems of degrading atomizer with loss of flavor.
Go to Google and do THIS search
site:e-cigarette-forum.com rokstar
That will pull up threads here that mention either rokstar or rok star. See what others think of it. But it's only sold in the UK so have you tried asking in the UK forum in National Forums of ECF?
And also - remember it's not going to be the only or last ecig setup you buy. Hopefully the
batteries are compatible with something other than what Rokstar sells in case you hate it too. Probably nothing wrong with the batteries as long as they have a compatible threading like 510 or KR808D-1 - do they?
BTW - did you ever read what I wrote the first time you asked?
http://www.e-cigarette-forum.com/forum/new-members-forum/276726-ego-rok-star-super-tank.html
But bottom line is - it's a UK product. Few here have used it. You may have to make your decision yourself.