I have had to replace the pull-tabs on the zippers on my smaller, newer Badlands packs with knotted cords. Almost every one of them has broken in short order. I haven't had an issue with my 4500, but I only used it on one trip. They look and feel sturdier than the smaller pack zippers though.
Strider: What did you use to replace the pull tabs on your Badlands with? Did you do it yourself or send the pack in for repair. I have 2 of the 2200's and the older one has blown just about every pull tab on it - no problems with the newer model at all to this point.