51 Raye Boals 7 months ago John, I haven't concluded yet that I really need them. I read online about how everyone suggests that strings pop out all of the time, but I haven't experienced that yet. I don't beat the strings on my guitars when I play, so I am hoping that this will not be a problem for me. I suppose that, like with the after-market bridges for Gretsch guitars, many will suggest that the Mastery provides tonal advantages. Thus far, however, I like the tone that I hear. But, I am open to making changes if the need arises. Bob, go with your gut on this one. After reading all your replies you are leaning to you don't need it, I think you are correct. The Mastery is a great bridge and is spectacular for a Bigsby equipped Telecaster. I love mine but on your two guitars where you have no real break angle or intonation problems, I think it would be mostly a cool looking piece of jewelry. As far as sustain there wasn't a real noticeable difference for me. I think your gut is telling you nah, for your guitars in question, and so does mine. If you get a bigsby telecaster I would say you really really should get a Mastery.