Its still wvga ( screen ). And who knows. Maybe it will become $100 dollars or something in 6 months. You never know. Having a larger screen and double the ram is not that much. The way I see it. The Lumia 820 is a better deal.
I think you should not go for 525 right now wait for some more months till wp8.1 arrive
I also have 520 and waiting for wp8.1 devices.
I think all wp8.1 devices will have 1gb ram.