I purchased those to fit my Yamaha YEV-104 strung with Infeld Red.
At the first glance, it looks like those pegs are too big for this violin.
It's however not the case, and those pegs fits very well on the YEV without the need to enlarge the peg holes.
Simply insert them, push them till the shaft is in correct position, mark on the peg where the outer edge of the peg box is, and get the dremel out !
The material is super easy to cut/grind and can later on be sanded to have a perfect finish.
It takes a bit of time, but it totally worth it.
I wanted to try those pegs to get rid of fine tuners on my tailpiece.
After an initial setup, it appears that indeed, it's super easy to tune the violin without fine tuners for G,D,A.
However for E, it's a bit tricky and I'm not sure that on the long run I would be able to skip the fine tuner for this string.
Even a very light turn of the peg can bring the E string slightly out of tune.
Infeld Red are coming with gold steel E, may be with another E string/another material this problem would be non existant.
My YEV and myself are very happy with this product !