I've been happy with DirecTV.
The thing that bugs me about Dish is that if they get in a tiff with a channel provider (example: Viacom) then they yank the channels and tell the customers to blame the channel instead of Dish. Also, if you watch the MLB network, then you don't want to switch because Dish does not carry it. With those "Dish has hundreds of the biggest NFL games each season" commercials, what they don't tell you is that it's exactly like having DirecTV without the NFL Sunday Ticket package, or having cable if your cable company carries the NFL network. But other than Sunday Ticket, Dish has all the other paid sports packages like DirecTV has (MLB Extra Innings, NHL Center Ice, ESPN Game Plan college football, etc.).
My understanding is you live in a mobile home that has a few years on it, so it probably won't be much of an issue, but here's how the dual-tuner receivers work: You have one box with an infrared remote for tuner 1 and a radio frequency remote for tuner 2 (that remote also has infrared to be able to work your TV and stuff, but the RF is what lets it work through the wall). The two remotes are labeled which is which. You have two separate tuners within the one box, which needs two separate lines coming from the dish. You then have the one cable line going to the TV by the box, and then another cable line that goes back out the wall and around to the room the other TV is in. That means three separate coaxial cables have to go through the wall in the room the box is located in. Having the dual-tuner box gives you the option to not pay the extra $5 a month for the second tuner, but you must have the box plugged into a phone line or else you'll be charged the $5 (the exact way that works was never explained to me when I was selling Dish but I assume there's an 800 number the box calls).
If you do switch, think about which channels on DirecTV you actually use and see if Dish has them all on a plan that's the same price or cheaper, instead of having to go up a tier to get a particular channel.