I tried some cheddar this weekend with apple smoke. It was definitely a learning experience! I followed the 20-min on/40 min off method, with ice, and it came out so-so. I did it twice, but it's not very smokey. Here's my analysis of my experience: cooker temp stayed ok with the ice in there - no melting. Not enough smoke - I think I used too big of a chunk, and it just didn't generate enough smoke in 20 min. I did see a little smoke coming out the blow hole (sorry, that's what I call it), and capped it with a glass when "off" (to hold the smoke in, but am not pleased with the results.
Plan for next time: Chips instead of chunks, and a little stronger wood (hickory?). It just didn't taste like I thought it would. Any ideas, guys?