I should mention one thing about the tie fast tool. It does poorly tying a knot when the line is thicker in diameter than what is being tied to. This is not usually the case in freshwater fishing however. Wet your knot before snugging it tight and even though you can snap the knot off the tool be certain you don't pull quickly to tighten the knot down.

This goes for any knot actually. A quick pull can generate heat which will alter the molecular composition of the nylon and result in breakage.

Be sure and test your knots often especially with 6lb line! It is very common for me after catching a bass in the 4 or 5lb class to re-tie my knot. If you just keep catching fish you will break off sooner or later (probably sooner). This is not very nice to the fish so check that knot often and re-tie. The knots do wear through (as well as the fine teeth on a bass having an abrasive effect on the line itself). Bass are quite hardy and will recover quickly so no harm done with the light line.