Usually when a new product hits the market to replace an older version there are always pros and cons. In this case however there are only pros.
Foam Tac:
Foam Safe (follow directions)
4oz bottle shelf life 2 years
Binds carbon and balsa quicker than ultimate
This is still not a CA but gives you that flexible long lasting non brittle build
The cost is close to half of what is costs per one bottle of ultimate
Now when you buy them in bundles the cost goes down
http://flyairhobbyrc.com/foam-p-664.html?cPath=71