Upgrade options?

Long story short I just found out T-Mobile no longer Carries xperia z3 Under warranty. They offered me a galaxy s5 as replacement, but I'm not a fan of that. So he told me upgrading was an option. Ironically I like the GS6. I also like the G4 and can't find any cons on it other than it being a big phone. My Z3 isn't broken, but has certain phone issues that have been around for a while. Speaker phone is just bad on both ends. Most recently it has been stutter stopping with text messaging, forcing me to restart 3 or 4 times before i get text coming in. I like my phone, but didn't know the "sony" problems before I purchased it. I'm trying to do a lot of research and get opinions before making another purchase.

Since T-Mobile isn't showing signs of carrying another xperia, I've been looking at the LG G4, GS6, and GS6 edge. I know a lot of you are phone collectors, reviewers, and just have multiple phones so I would like some honest opinions on these phones compared to the Z3 if possible. Rooting, every day usage, common problems, if it's worth, etc. These would be greatly appreciated everyone.