I feel like they're all great -- any of the top four (of Masters, Lamon, Brnovich, or McGuire) would make an excellent candidate. I wish we could redistribute the AZ-Sen candidates to other states; they're somehow all better than anyone who ran in Ohio or Oklahoma. Even Olson is really just colorless as opposed to particularly bad in some way.
On an RCV ballot, I would first-preference McGuire. I think this is shaping up to be a race between Masters and Lamon, and of the two of them I think I'd support Lamon, merely because people I dislike within the party tend to support Masters, but Masters himself honestly seems fine and he would be in no danger of losing my general-election vote.
How is someone who said "privatize social security" a good candidate. You may agree with this position but that doesn't make it a good thing to say on a campaign trail
I think he is a good candidate in the sense that he has some experiences and ideas (regarding futuristic technologies, for instance) that I think would be valuable in the Senate, not necessarily that he's super electable. This is similar to my rationale for supporting Mehmet Oz. (Incidentally, it's also true of my rationale for liking Jim Lamon: I think a solar-power magnate would be a very valuable voice to have in the Senate!)
I agree that Blake Masters doesn't necessarily seem like the strongest possible candidate from an electoral sense, and this is maybe part of why my own hypothetical vote is probably for Lamon. Social Security should be privatized, of course, but it's off-message for 2022 and could be better sold by an older politician with a more deprived background (thinking of Virginia Foxx here), as opposed to a young rich VC guy.