3M super glue gel is the best I have come across so far. The one from GARF seems to be pretty much the same, but it's in a bigger tube. Unfortunately, I haven't been able to find the 3M gel in bigger tubes.
I bought Karzy gle not the gel kind, and it said Contains ethyl Cyanoacrylate that is good then right. Just wonder do to the fact that none of you guy's said ethyl in front of Cyanoacrylate. TIA.
The big thing to remember is to pick up the gel kind and not the standard kind as the standard is way too watery to work well. As long as there is cyanoacrylate somewhere in the name you're set.
Keep an eye out for Zap Gel which can be picked up at many hobby shops. It's very thick and excellent for mounting SPS frags. With a quick google search you can find vendors selling it in bulk which is fairly cheap.
Reefland I just bought 5 7oz bottles of this stuff form Premium Aquatics did the search on googles and that is the one that had it. Many others but I have dones business with them and like them.