Something's not right there. I have been running a $60 Brinkman POS for three years with pretty epic results. There is an even-more-cheapo version than mine, which does not allow the 'body' to be lifted off the fire bowl.
Tim Walsh of this board has one of those, and yes, he made some really cool mods to it, and it now functions as well or better than mine. Do you have a lift-off body ($60 Brinkman), or the one with the cheesy 'legs' at the bottom ($40 Brinkman)?
All that being said, he and I can easily run a three-hour smoke session without having to tend the fire.
Sounds like you might have a new unit that isn't sealing really well. Whip up a sausage fatty and smoke it for 5-6 hours - build up a nice layer of black fatty creosote on your unit. That will help insulate and seal it.
Tabs is likely to weigh in here with a lecture about 'you get what you pay for', and he's right. However, these cheap smokers can produce truly unbelievable results. Not only that, but I can (and DO) toss mine into the trunk of my car and take it over to my parents or to the racetrack. Try that with a $2k smoker :]
I have turned out everything from BBQ chicken thighs and sausage logs, to masterpieces like standing rib roasts and whole turkeys, using my POS smoker. I love the damn thing.
BTW - I stopped using chips. Unless you fret over them with soaking and making foil 'packets' to make the chips last more than 90 seconds, they are a complete waste of time/money. Get nice chunks of wood that will last a couple hours - your guests will thank you, and you will spend less time diddling with the smoker.
The added benefit, is you don't have to waste time soaking the chunks.
Gawd I love these smoking threads