Here's what I like, pickups from JJB Electronics. Made in USA, fast delivery, awesome support. I've installed 2 of the Prestige 220 (one in a mandolin)and one Prestige 330. Highly recommend them. jjb-electronics.com/our-products.html
I’ve mentioned this before, the techno geek inside of me has to reverse engineer nearly every thing I get into. The first transducer I used was a K&K, it was put into a cigarbox bass I built. I got the parts from Owen Holt of Road Toad music, lncluding the the tuners wide enough to use the Pahoehoe strings, he was the guy who came up with the Pahoehoe strings and the first bass scale ukulele.
When I started with these projects I researched transducers. What I discovered is transducers are transducers. I found zero information concerning any functional differences between transducers, I found no information on manufactures or variation in properties or quality. The only difference and information I found was disk diameter. It apprears that smaller disks are used in smaller instruments and larger discs used in larger instruments. For under saddle transducers I only found one reference of the material and it’s the same material that is used for triggering and counting traffic at traffic lights and tolls, installed under the blacktop.
So I ordered a bunch, unwired el Cheapo transducers. I’ve been using them. I ordered the JJB set for the guild B-50 because it was a decent price and included everything, install and play. I’m not sure I could tell the difference between a 15 cent transducer and a $100 K&K.