You are going to get as many answers as there are folks fishing 4 weights. I have a Sage xp 486 4 that I love but it is the only 4 weight I own so of course it is my favorite. Best thing to do is to go to your local fly shop if you have one and try a few out. If you don't have a fly shop handy I might suggest joining a local fly fishijng club and try the membership's rods. What I am getting at is you need to put a few different rods in your own hands to see which one is right for you.
"The reason you have a good vision is you're standing on the shoulders of giants." ~ Andy Batcho