Kaytee isn't really that good. Doesn't have as much nutrition. Try getting Oxbow, it can be bought at the store. The best hay for guinea pigs I think is from Kleenmama's hayloft http://www.kmshayloft.com/catalog/. Its very green and soft and the pigs LOVE it, it's also cheaper if you buy in bulk and store it. You can keep it in a big plastic bin with the top off, so it can breathe. The only downside is it can only be bought online, it takes about 4 days to ship. Get 2nd or 3rd cut though, they are the best :)
I've heard great things about Oxbow hay, so I'd try using that. Before purchasing the larger bags,just buy the smallest one that they have to make sure that you like it. Good luck with finding new hay!