I really like mine, although I honestly only use it maybe five or six times a year. Mostly because the things I cook most often - mainly chicken and ribs - I can do just fine on my Weber kettle without having to go through the ritual of lightning the smoker and cleaning it up afterwards. I use my WSM for things like pork butts or shoulders, brisket, and turkey. I'm gonna try making my own bacon next.
As far as temp control, it really maintains itself for the most part provided it's not very cold or windy outside. You may find that it'll be a little hard to maintain a steady temp and/or it'll run a little on the hotter side when new, just the nature of the beast until you get some char and fats and grease built up in it.
I normally light my cooker using the Minion method with regular blue bag Kingsford briquettes. With the fire ring filled about 2/3s of the way with unlit charcoal and about a chimney of lit briquettes on top, I get around 12 hours or so of cooking time holding pretty steady at 225-250ish degrees depending on what the outside weather is doing.
You'll probably find that the thermometer in the lid ain't all that accurate, and within reason I think that's okay. I have a Maverick wireless thermometer I've been using, but I got tired of messing with it, had a run of probes going bad, it'd lose connection to the remote display, etc., so for most things I really don't even care what temp the cooker is actually running. For butts or brisket, so long as I'm in the neighborhood of 250-300 I'm happy, and I check the meat every so often with a Thermapen anyways so F-that on the remote digital thermometer thingy. I do care what temp the cooker is running with poultry though, I like to run it hot to help crisp the skin up, but not so hot that the bird gets nuked and overcooked.
I fold up a sheet of tin foil and half assedly line the water pan with it, it makes clean up easier after everything is said and done. I also burn mine out after I'm done cooking, run the vents wide open, add a little more lit charcoal if necessary, and scrub the grates down. Sometimes mold can grab hold of the insides depending on your weather/humidity and how often you use your smoker, so I make a concerted effort to burn it out and empty the ashes as soon as possible.