Don't Fuzz that often but, got a hankering to do more!
I've got a JHS mini foot which I believe is silicon transistor.
I'm currently waiting delivery of a Mini Fuzz Face Jimi Hendrix version which I believe is also silicon but slightly different.
Depending on how that performs, I might go shopping for a germanium fuzz.
I recently tried something different with the mini foot.
I dialed the fuzz to the max, expecting it to be completely out of control but I was pleasantly surprised to at the tone it delivered.
Here's a couple internet quotes on silicon vs germanium:
"The earliest fuzz pedals used germanium transistors, which is why there is a strong a sense of nostalgia for these with old-school purists. Germanium Fuzz boxes tend to produce a warmer and more-rounded tone with a strong mid-range, and are generally more reactive to your picking dynamics and playing style.
Their tone is comparable with the early inspirations for the effect, producing a similar sound to a cranked faulty/old amp. Germanium fuzzes also react well to the volume pot on your guitar, with the level of hair reducing when you roll the control down.
There are a few cons with germanium transistors though. For example, they react to changes in temperature, which affects their sound. So playing in a hot room or studio will make the pedal behave differently to playing an outside gig in the winter. Many believe they actually sound better in the cold, but we’re not going to suggest putting yours in the fridge! They also store electrical charges, so there is generally a lack of consistency and they can sound different day-to-day."
"Silicon transistors were developed to be a more practical alternative to germanium, offering more reliability and consistency. Simpler to produce, silicon fuzz pedals are generally cheaper and deliver a brighter sound with more presence and top-end – allowing players to cut through busy mixes and get heard.
They also produce higher amounts of gain, giving you a more “in-your-face” tone with plenty of saturation. Unlike germanium, when rolling down your guitar’s volume pot the fuzz tone will remain and only the volume will drop. These days, most makers of fuzz pedals will use silicon transistors because of their availability."