I've tried the seed mixes there. I liked it well enough but I think it has more grasses in it than anything else. Right now I'm trying out the testudo mix from tortoisesupply.com but it's too soon to tell. Comparing what I see out of tortoisesupply.com's mix vs. carolina.. I'd have to go with tortoisesupply. There are other sites out there but I've never tried 'em out. Maybe more people can give you reviews on other places or the ones I mentioned.
Thanks! I actually just looked and bought the dry-climate mix. I have a Leo but they were out of the mix they made just for African tortoises so I just bought the 2nd best!