I have been using a FastFlight Flemish string (16 strands built with three bundle design) on my Hornes longbow.  I have been looking at some of the TradGang sponsers that make strings and their fast flight strings are a two bundle design.  What is the difference between the two bundle vs three bundle design?  Are there performance issues?  Is one design better than the other?  I know this is probably a newbie question but what better place to learn.  Thanks.

No difference other than appearance. Both shoot fine.

What Roy said...

According to T.J. Conrads in his book "The Traditional Bowhunter's Handbook" He says it makes absolutley no difference...they both perform the same. The three bundle makes a more rounded string but that that is simply preference in the look.

Thank you.

From a,engineer friends perspective. To make a round cable or string you have to have an odd number of strands or bundles.
Makes no difference in performance.

A three ply string is 'rounder' and a little more time consuming to make.
With modern string materials it doesn't make any difference but if you ever make traditional string you will notice three ply will last longer due to outer fibers being more evenly stressed.