Ok, I am going to be slightly biased and say cpanel because I own a few cpanel licenses
But to be honest, I have used plesk, cpanel, and ensim in the past. Ensim was ok, did what you wanted it to, but didn't have a lot of the bells and whistles of cpanel at the time. Plesk, used that for a good 8 months or so, and thought it was decent. It was fairly straightforward, no flashy graphics or icons, like Ian said, kinda like threads. But at the same time, I think the learning curve was a tad higher than with other software.
Cpanel, well, I guess it is sort of like the windows of control panels. It has a ton of features, a very easy to use GUI.. but at the price of more frequent bugs than some others. Typically though, like windows, these bugs are minor and fixed automatically with the cpanel updates that run nightly.
All of my servers run cpanel, but not as much for the admin useage, but for the clients. The actual admin area of cpanel is called WHM (Web Host Manager). This is easy to use and powerful, but the strong point with cpanel is how it appeals to hosting clients and the ease of use packed with a lot of features.
So it is a tough call Josh, it depends on how comfortable you are with server administration, and of course, price. If you want to find out even more opinions, check out the control panel forum at
www.webhostingtalk.comThere are always debates going on about the various control panels, and you can read many good reviews about each of them
