If you are wanting to climb really steep hills, the RTV will not do that. I have some very extreme hills and have done numerous test runs with my Rhino and my RTV. The RTV will climb moderate hills, but no tire will help with really steep hills. You will flat run out of power with a tire that grabs really hard. My Maxxis Bighorns provide more traction than the RTV will turn on hills. If you want to climb really steep hills with the RTV, you will have to find a way to provide considerable more power.
With that said, I can tell you that the Essex lift is fairly easy to install on the RTV. The trick is to remove the front struts when installing the front spacer and then re-install the struts. I spent quite a bit of time trying to get the spacer in with the strut compressed but on the RTV. Won't work. Otherwise, the lift looks good and I have no issues with it.