Well the pellets are alfalfa based, which is no good for adult cavies (or non-pregnant cavies). Both companies also sell timothy based pellets.
You are right, timothy hay is the choice of hay for the piggies and provides the fiber for our friends, but Kaytee is generally a poor brand. Their hay is old and doesn't hold nutrients in the same way that a nice fresh bail would. Hence the suggestion for Oxbow or KMshayloft.com Kaytee is also harder and more difficult for them to chew compared to the other brands.
The pigs KNOW the difference, trust me. After I learned about KM's I purchased some (I too was using Kaytee) and they went nuts. Their coats look nicer as well.
very nice cage, i first adopted franklin for my granddaughter and then adopted a mother and daughter and a father and son from a lady that was moving and was going to just leave them behind. so they are in three cages now until this weekend. could i make a 2X6 and divide somehow ( 2 females and 3 males) until i could build another big one for the females. would that be ok for now? i never knew guineas were so sweet and cute!!!