HowdA... Great question...
Strength is a very subjective quantifier.
Generally speaking, since Fabric# is an enhanced wrap system, it comes from the cyanoacrylate family. This family of acrylics offer great adhesion and flexability... but they are still a simple polymer....
Radical and Retention+ are reinforced cross linked monomers from the methacrylate family. They offer superb adhesion and maximum strength.
Where Fabric# shines is in its multiple grade of resins... it makes it much harder to create weakness within the finished product like you can with a l&p system... therefore Fabric# can end up being stronger than many L&P applications (though this is more down to technique rather than technology).
Hope this helps