to SatelliteGuys...and moved to C-Band forum, pretty much any C-band Lnb below 20degrees or maybe even higher depending on the size of your dish ( 10'?) and how well it track's the arc...
I bought Eagle Aspen's for both my c and ku feeds. They have been in use for a few years (north east heat/cold)with no problems. I here the Norsats are really a cut above but they are costly. I'm saving up for the Norsats and when I get them I'll keep the Eagle Aspin's as spares.
For C-band the Norsat 8215 is great, and for Ku-band the 4206a is nice, for 4dtv you can also get away with the 8515 and 4506a, but if you may be adding dvb or if you dish is under 10' the others would be a good choice, you can also go way out and grab the 8115 and 4106a but they are way over kill for a 4dtv only setup.