I spent years with the same problem and tried most of the old ones as they came on the market, including a tiny Sony microphone that just fitted into the round part of the F hole and various ones that stuck on and ruined the polish on the instrument. My problem was that I didn't want the electric sound that bands like Fairport were getting. If that's what you want, most of the brands on the market are pretty good. The one I ended up with (and still swear by ten or more years later) is the Fishman. It's a little folded brass/copper thing about a quarter of an inch square and it fits into the cut out curt on your bridge. I also reamed out the underside of the chinrest to hold the jack plug so there was no need to attack the actual fiddle itself. After a yaer or two the first one I had broke at the fold. This was mainly because the tension in the fold is what keeps it in and I took it out a lot to try various places. The remaining part was still very serviceable but would no longer fit in the bridge. I tried sliding it under the bridge and it worked quite well, but not as well as the original so I had to but another. They're not cheap! Fortunately, I then discovered that the old one when slipped between the velum and the foot of the bridge of my banjo gave me a great banjo sound. By that time I had given up trying to find a good banjo pick-up, or at least, one that suited my taste. The only other thing I found was that you need to experiment with DI boxes and the input control on the mixer. If they overdrive the input, they sound terrible and this was always a problem when using someone else's pa, like at a festival. This could probably be overcome these days by the great range of pre-amps available, but I found that a passive DI worked best for us but then the rest of the mix needed to be set around the fiddle, no problem if it's your own gear every night but fun if not. Hope all this helps. Good luck!