First, I'd like to emphasize that, AFAIK, this applies only to the "Arista" products that have been discontinued. Freestyle is continuing to use the "Arista" name in reference to rebranded products made by others, such as Foma. I believe that "Arista II" and "Arista.EDU Ultra" are their current lines (made by Agfa and Foma, at least for film, if I've read between the lines correctly), while "Arista Pro" and "Arista.EDU" are discontinued (made by Ilford and Forte, I believe, at least for films).
Second, be aware that some of this clearance material may be pretty close to expiration. I bought some 100-foot spools of Arista Pro 50 (aka Ilford Pan F+ 50) recently, and the boxes have expiration dates of 2/2006. Thus, if you buy this clearance material, you might want to be prepared to use it all quickly or freeze it. Personally, I've got three 100-foot rolls of that Arista Pro 50 in the freezer and a fourth carved up into 36-exposure rolls, about half of them used. At $17/bulk roll for the Arista stuff vs. $40/bulk roll for Ilford Pan F+ from B&H (or $43 from Freestyle), it's hard to pass up the "Arista"-branded stuff, even if it's short-dated!