I swear by CG's for my SYMs, but on the 500 I'd double check to make sure the weight range is correct for the heavier bike.
Far as wear goes, this will vary by a variety of factors.
I got 10k+ on one rear before it took a nail and busted a cord, but that's on a lighter bike so YMMV.
I used to get 7-8K on Shinko rears on my burgman. More on the Michelin but not enough to justify the cost difference.
Looking forward to how this works out. I kinda watch for AK550s among other bikes for when my SYM ages/miles out.
I ride straight up & down, not a corner carver. Last year I put a Shinko tire on the back of my 500. It's pretty thin after 6K miles, and it cost about 80 bucks. So I ordered a new tire & it arrived yesterday at my dealer so I picked it up. It looks like a real mean piece of rubber, it's a Michelin City Grip tire. I went for that specifically because so many scooter guys swear by it. But it was considerably more money and I'm wondering if I'm likely to get good life out of it.