Heck, I'm still waiting to get LTE in my neck of the woods here in Florida. Consider yourself lucky that you have it. I've had a few 4g phones and haven't had LTE yet except when travelling. I've been on hotel wifi and LTE in Jacksonville, LTE was blazing.
On my Thunderbolt I never really saw much of a difference between 3G and 4G (Speedtest.net speeds were essentially the same, 3G at 1mbps, 4G never went over 5mbps). Plus 4G drained my battery about 50% faster. The Nexus is totally different. 4G speeds are noticably faster at 15mbps. I leave 4G on all the time and my battery still lasts me from 7am to 11pm every day. I definitely notice the difference in situations like at the gym, where I stream Netflix for about an hour.
I live in an area where I get 4g, so my husband bought a Xoom tablet 4g this past Thanksgiving for me. I then got the Razr Maxx for the leap day sale. I never had any problems with 4g until April 27th, now all I get is 3g. When I leave my home I pick up 4g about 2.5 to 4 miles from my home. When coming home I lose it just after turning down my street. The closest tower to me is .8 miles away. I have been on the phone with Verizon 3 times in the past week and 2 people started a ticket on this and I have heard nothing back. Any suggestions? Also I did get the update a few days prior to 4g going out near my home and this also happened on my Xoom tablet (losing 4g).