I have both, and I much prefer the MVP. Both are beginner friendly.
The MVP is rock solid and has been a proven performer in the long term. The only issue I have had with mine is that the center pin gets pushed down and needs to be pried back up. If you have the patience, Innokin will be releasing version 3 by the end of the year. They will have several variations, but they will all be an improvement over the 2.0, including a spring-loaded 510 connector which solved my only problem with mine. It will also have a larger battery, an improved fire button, and the charge port will be on the side. Innokin will try to keep the price low, as that has been one of the main reasons for the success of the version 2.0. If you think the V2.0 is good enough, 101Vape is still the best place to buy -
Innokin iTaste MVP V2.0 - 101 Vape
The iStick form factor is fantastic, but there are way too many problems with it for me to recommend it. Inconsistent power throughout the charge cycle, incorrect power regulation, threads that wear quickly or destroy the threads on your atty/clearo, and generally bad build quality. I have relegated my iStick to use only with certain clearos and only with the adapter attached, and when it dies, I will not be buying another. IMHO the idea behind the iStick is great, but the execution leaves much to be desired. Probably why eLeaf is already working on a version 2. Then again, the iStick still has a dedicated following of people who are happy with theirs, so take my gripes with a grain of salt. You may want to pop into the iStick thread here on ECF -
http://www.e-cigarette-forum.com/forum/variable-voltage-apv-discussion/601111-eleaf-istick.html