Mike, all tho the MES units do have large temp swings the act of smoking foods practically pork allows the swing, What I mean is that pork cooks well with them. I just wanted mine to be 242 if I set it at 242. Do you have a gen 1 or gen 2 style unit?
My smoke lives on a concrete pad elevated behind my house. It is covered and I only use it when it is dry. I do however remove my controller. It is very easy to do I just unplug the smoker and the power cord. The probe unplugs and is stored in the smoker. My home has vinyl also and I thought that may be a concern especially when l one of my neighbors had a propane grill to close and now had drooping vinyl. The MES units don't get to hot on the out side I keep mine 6" inches from the house angled away from it. Use your temp gauge to monitor the heat at the vinyl I never had any issues with it. I spent a lot of time checking mine and the hottest area was the door seal, and the top near the exhaust. That is where you would expect it to be the hottest. I did my checks in July and August. Always error on the side of safety. If you are concerned you can buy a peice of concreat board and just set it behind the smoker. $13.00 and it is no longer a concern.
http://www.lowes.com/pd_60358-34299-220023_0__?productId=3067737&Ntt=hardy+board&pl=1¤tURL=%3FNtt%3Dhardy%2Bboard&facetInfo=
You can find PID units on
Amazon and Ebay but you must assemble them. There may be other plug and play type controlers but the Auber is the most used with smokers. Look around this and other sites for the info you need. Since I don't know your level of expertize I would not recommend it.
I must say that smoking meat as a hobby has been like most other hobbies a money pit. It is not like having a boat. You can spend a lot of money. If I had it to do over I should have started with a MES 40 instead of a 30. It is just my wife and I know but I never smoke for 2 it is usually 5. It's amazing how fast they come home to smoked meat.