Debating getting an A57 (Yay or Nay?)

I'm thinking of buying another Alpha. I currently have four. (A200, two A500's and A550) It's worth mentioning that I am on a fixed disability pension, in other words, not exactly in Thurston Howell III's league. I have had my eye on the A580 for quite some time. It was never available in Canada for some odd reason, but I could buy from the US, which in the end would cost me close to $1,000. (incl shipping/duty/brokerage, etc) But... I have discovered from browsing the Sony Canada website that the new A57 can be had for a mere $699. I also realize that this is less than HALF what I would pay for an A77. HALF!!! (and about $350 less than an A65)

To be honest, I don't give a rat's you-know-what about a sensor over 16mp. I would, however, like low-light performance that is at least as good as my A500 and A550. I understand that the A57's IQ should be pretty close to that of the A580, which should put it a bit ahead of the A500/A550. So... IF I was able to get, say, $400 for my trusty A200, I'd have that lovely A57 in my bag for only 300 bucks. Does this make any sort of sense, or is it strictly another case of G.A.S.?

So... it basically boils down to this. How easy/difficult would it be to try to justify:

(a) - paying about $300 more for the A580 over the A57
(b) - paying about $750 more for the A77 over the A57

My tired brain tells me that the A57, at a mere $699, is a pretty sweet deal; has the kind of goodies I am looking for in a camera, without a bunch of extras I don't need. I would love to hear your thoughts! Try putting yourself in my shoes; (I know; it's a scary thought) and keep in mind that you'd be looking for the best bang for your buck, without breaking the bank. And while we are on the subject, what could I realistically expect to get for my A200? (perfect condition with very little use) Really, I almost hate to part with it, but when I consider that the money I could (hopefully) get for it could put me within just a few hundred dollars of a shiny new A57... well, I'm maybe starting to feel a little less attached to it!.

Thanks,
Glen
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