I've killed two of these over the last 8 years. They are absolutely superb at what they do, although hideously over-priced!
If I could offer my own advice, think about how you want to smoke first, as there as a couple of things the Bradley is particularly suited for. 'Warm-smoking', such as when you want to produce a cooked sausage, Tasso, Summer sausage, pulled pork, brisket, etc, is a particular strength of this unit. If you want to do any of this type of smoking go for the digital controller, as you can control temperatures and timings far more easily than with the analogue version. Having said that, I've used mine to successfully produce pulled pork, smoked sausage, chicken, turkey, among many other things. Just don't expect to cook things in half an hour and you'll be fine. Pay attention to internal temperatures too!! It's a whole other facet to cooking (apologies if I'm teaching you to suck eggs though) Invest in a decent wireless temperature probe, too. It'll be worth its weight in gold. And learn the correct use and dosage for Cures 1 and 2. You'll often be right in the danger zone for botulism growth, and this will prevent the spores developing and keep your food safe. It's nothing to be afraid of though, just be wary.
For cold-smoking, you'll not go far wrong if you invest in the cold smoke adapter (although bear in mind that Bradley, in their infinite wisdom, have made the bloody door JUST too small to allow you to place the bisquette bowl in without tipping it on its side (don't get me started!) Ambient temperatures have an effect on the cabinet temperature too, so it's worth bearing this in mind for smoking fish, eggs, cheeses, etc. If you don't want to smoke during the cool of the night, you can always place a couple of frozen 2l water bottles in the cabinet, and this will keep temperatures where you need them (below about 22C) Read up on brining, too. You'll NEED to know this technique, and it makes a hell of a difference to the result.
As far as practicalities go, keep the bisquette tray clean (scrape with a wire brush now and again), keep the feed chute free of debris and particles too. I place a foil tray above the heating element to protect it from grease (but it's a good idea to have a couple spare. When they blow, it'll be right in the middle of a cook, you can guarantee it!) Make sure you brush carbon buildup from the roof of the cabinet too, to prevent it dropping onto your food, and I'd ditch the useless baffle thing on the exhaust port too, and blank it with a piece of flat steel instead. Keep an eye on your door seal too, as they have a habit of coming adrift, and don't trust the built-in temperature probe. It lies! It's also a good idea to spray your trays with an oil prior to using them, too. It just makes cleaning them slightly easier.
Oh, and a couple of heat bricks inside the cabinet will allow it to come back up to temperature a lot faster when you've opened the door.