Another vote for the Amazen products.  I have the 12" tube and the 6x8" pellet smokers.  The only limitation I have is the ambient outdoor temps.  These products do produce some heat, but thats is not really an issue if its cold out.  I wait for winter time and have no issue at all keeping the temps below 85 degrees.  I'd love to do some lox or gravlox, curious if it leaves a fishy smell in the cooker?  Not sure I'd like that...