I have had V8S and V9S and Zgemma and to be perfectly honest with ya, the V8S and the V9S are alot easier to use as in more user friendly. The Zgemma looks like ya need a Science degree to use all of it functions unless you load a pre-made build. But even then you will need a good memory to find everything,,,,, Thats just my opinion. Others might find it easier to use than me, but the V8S and the V9S are a doddle to use.