Bora-Care and Timbor are both borate products used to treat wood, but they could not be more different.  Timbor is in a powder form that is mixed with water.  It is much less expensive but it is intended more for protecting new wood only, or wood that you know does not have any issues.  Timbor will only penetrate the outer layer of the wood (about 1/4 inch) so it is more for protection or for treating fungus on the surface of the wood.

If you have an active infestation of termites, powder-post beetles or wood borers deep inside the wood then Timbor would not make it through the wood to kill these insects, up to 4 inches with one application or 8 with 2 appliations.  BoraCare is a liquid borate but has an additive, a glycol solution, which allows the product to penetrate through the entire piece of wood, therefore it should be used any time you have an active infestation because you are guaranteed it will kill anything in the wood no matter how deep it is.  Also, BoraCare will last forever in the wood so you will never have to worry about any infestations in the wood that you treat ever again.