Honestly, it depends on what you want to do with the phone. Do you need a phone that works really well, or do you need a phone that can do everything?
Do you need a phone that is fast, reliable, and smooth, does basic chat/SMS/facebook and integrates really well, and Does OKAY with point and shooting? WP7 is the best.
Do you need a phone that has the latest and greatest applications, has more stuff, does the previous stuff fairly well, has the best hardware, but loses reliability and smoothness? WP8 is for you.
Keep in mind that it won't be upgraded and won't continue to have support. But I don't really think it needs it because it is a really reliable phone and it can stand on it's own two feet.
It really depends on if you need the applications. If I didn't need applications, I would go back to WP7.