1-BS I would put Rival ahead of 105 and pretty close to Ultegra. I can't imagine that any would be more or less durable than the other.

2,3 Both BS- Most name brand bikes in the same price range will be pretty much equal in build quality. Differences in ride quality will be mainly in geometry.

4- For an experienced cyclist a test ride may not be important. Most could look at the geometry specs and have a pretty good idea how it will ride. A new cyclist should test ride several different bikes in ranges of sizes that may fit. No one can look at you and say you need a certain size and always be correct. Try some that may seem small and then go the other way and try one that may be too big until you find out for yourself what is your correct size.