All depends on personal preference really......the little/big chief works well enough for basic smoking but yes some do have problems with maintaining correct temps, over/under heating and such...but good cost as well.
the bradley you are not looking at much for problems really and especially if you go with the digital bradley as it is just a "Set and forget" type smoker and you dont have to watch it all the time temp/burning wise. Much more options, better temp consistency, better temp controls, higher and lower temps able to be maintained....but the cost is much higher and with bradley smokers you have to use their pucks but there is TONS of flavors.
As someone above mentioned.....also would depend on how much smoking you are planning on doing......or what kind of budget you have, lol.