From what I gather, you should use a 301 redirect most of the time if a page has moved permanently (all redirect links (new permanent location) get the rank in search engines).
A 302/307 redirect could be used for temporary redirects (e.g. if you've moved pages due to maintenance purposes). These types of redirects DO NOT take any link ranking with them - so SEO shouldn't be affected.
Now for the difference in 302/307. To my mind they're pretty much the same, BUT 307 will only work on HTTP1.1. 302 will work with both HTTP1.0 (Moved Temprorarily) and HTTP1.1 (Found). So on balance, I'd use 302.
I'm no expert on this though, and I'm sure other contributors could give you a better description/ better insight.
diafol
Rhod Gilbert Fan (ardav)
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diafol
Rhod Gilbert Fan (ardav)
7,792 posts since Oct 2006
Reputation Points: 1,170
Solved Threads: 1,080