6.1.2 - Switching from LTE to 4G randomly! ??

I have 6.1.2 installed on my Iphone 5. Basically here's whats going on.

-LTE will randomly turn off and 4G will be enabled. Even when you go to Cellular, LTE is switched on... but it's not on.

-Wifi is a disaster for me. The signal drops in the same room as the router. I don't know how to explain the problem other than a CRAZY WEAK WIFI signal. I don't really know what to do about this. I've literally had 6 iphone replacements with 6 different issues that came with them. They refuse to exchange anymore. I don't recall this wifi being an issue on any of them prior to this one. I'm hoping it's not hardware but, signs are pointing toward it being so.

-Battery seems better than in September when it would just die in standby.

While, I appreciate some things being fixed, I don't appreciate a company who basically gets fed up with helping somebody with their purchase. Why did I have to get 6 iphone replacements?? Oh, that's right - because they are making these phones like garbage! Scratches, Buttons improprly built that cause malfunction, wifi problems, camera problems, BAD BATTERIES. But when it's all said and done, they refused to just keep on exchanging until I got what I paid for. I think that's crazy. The fact that I was loyal enough to say, Okay, let's try it again - instead of saying THIS IS PEICE OF GARBAGE PRODUCT (Which, i'm sorry, it is) speaks levels of my loyality. I was dismissed from their care and I think that's ridiculous! Sept 21st purchase, it's now Feb 23. I STILL HAVEN'T GOTTEN WHAT I PAID FOR! Thats the truth.