Hi, My name is Alan.
I’m new to the art of knife sharping. I join this forum, to find out which unit would suit my needs.
I fully agree with Bill’s comments. The Gen 3 vise is very nice, but the Gen2 vise gives up very little of the convenience and handles blades thicker than 3/16". The Gen 3 vise easily clamps FFG knives, but the Gen 2 can be made to work. If you only plan to sharpen a few knives per year, the base system is OK. The upgraded arms give you a better pivot joint for the arms, but the real payoff is the ability to make very small degree changes easily using the built-in microadjusts.
+1 for at least the better pivot arms with micro-adjustments. Most everything else is budget and OCD level dependent IMHO. 
Hi Alan, welcome to the forum! I agree with the other guys: I’d get the upgraded arms. And then which stones to get, that’s dependent on the budget. Eventually you’ll get them all 
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