I own an eGrip, it rocks! Nice and small, but lacks the bigger battery and vape time of the iStick. The downside is the price of the coil-heads, they are on the pricey side. The upside is that Joyetech is now making rebuildable heads (I ordered one) thus allowing you to build your own coil heads if you wish to do so.
I bought a couple Protank Mini 3's when a vendor had them on sale for $4 each. Bought 2. Used one for a day and then gave it to my brother and the other to a girl at the office who uses Ego's. Not enough airflow for me, plus the flavor wasn't what I expected.
If you are going to get an eGrip, get it from vapenw.com. The Joyetech website has a problem with someone ripping off credit card information and committing credit card fraud.