the only things I don't like about the pro is 400 watts for each of the 4 lines out. and if it goes down so will a lot of racks. the herpstat ll is 700 watts for each of the 2 lines out and even if buying 2 of these will be a little more, if one breaks you are only losing half as many racks and might even be able to power the others being the 700 watts per line, until you get a new unit. I have a few herpstats and I know that they rarely break. just something to consider and find which is best for you.