OP, I think you may be making this decision more complicated than it is.
Typically a Mossberg500 and Rem870 are the most common and reliable brands within a reasonable price range. there are the lower-priced SG's like the Maverick, and higher-dollar ones like Benelli M4 etc.
For the most part if you stick with a well-known and reliable model you should be ok. So just pick one you like that is within your budget and go from there.