I shoot the Vortex and love the thumbhole stock. It's relative shorter length makes it easier to cock but (either) is a 200 lb draw weight bow, so if you have concerns about being able to cock it step down to the Phoenix. I find it relatively easy to draw (have had 2 back surgeries) with just the string cocker. I'd try that first, since you'll need a string cocker no matter what you get to ensure that the string is centered when cocked. You can always get the much more expensive mechanical cocker if you find that you're unable to get the job done with the string cocker. BTW, I made the mistake of investing $125 in a mechanical cocker only to find that I don't need one.
A tip you may benefit from: shorten the string on the string cocker so that you have to pull the bowstring up about 2-3"s or so to hook the weak side hook. That makes the distance you have to pull the string cocker shorter and therefore makes cocking easier. Plus, so rigged, it stays in place even when you transport the bow.