I started seeing the LTE icon last Friday when I was downtown. It was in and out, but I didn't think of doing a speedtest at the time. I did see a difference in speed when I had it, though. But on Monday at work, toward the end of the day, I noticed a 4G icon for maybe a minute. The speeds were pretty fast, but it quickly went back to 3G (and noticeably slowed down) and I haven't seen it since. :-(
I'm wondering, why was I seeing the LTE icon on Friday and 4G on Monday? Isn't it basically the same service? Does it vary with where you are? I work in the NW part of town about 15-20 minutes from where I was downtown, so IDK.