I got an OEM version of Nero I use for a lot of burning but when mounting disc images (especially when checking DVD images I've authored) it's great to have Alcohol 120% be able to mount it, check how it runs, then burn it all in the same program. Easier to stay within one program because Nero sucks with drag and drop burning of disc images as well so I mostly use it to burn data discs.
If you don't mind not being able to burn a disc image using Daemon Tools, it's arguably the best disc image mounter and it's price absolutely can't be beat. For me, I find Alcohol 120% eases things for me and speeds testing of images so it's worth the price.