I'm surprised, on perusing this thread, that nobody has recommended Smokin-It. In case anyone is still looking, I'll offer my opinion.
I have one of their Model 2 analog units and I'm very happy with it. I've had it for 3 years and it's been stone cold reliable. I've smoked port butts, briskets, ribs, and (hot-smoked) salmon with consistently very good results. It's not cheap even though it's made in China, but it's very well built. It's also very economical on wood chunks. I've smoked large briskets for over 20 hours with just a couple chunks of wood and never had to open the door.
Like any of their analog units, temperature swings can range from 20 to 30 degrees during a cook but I just adjust the "thermostat" to get an average temperature that I'm aiming for, and results are consistently good. If temperature swings bother you, they offer "digital" units to control box temp much tighter.
My smoker can't do "cold" smokes, but they do offer models that can cold smoke if that's something you'd like to do. Someday, I may mod mine so I can cold smoke salmon, but I've got a lot to learn before I go down that road. Meanwhile, I'm perfectly happy with my Model 2 and recommend it highly.
Good luck!