300 Below is by far as Cryo goes.
I highly recommend that anyone who who has a Mini spend the money and send your barreled action to 300 Below, especially if you have a skinny barreled mini.
The cryo really helps the accuracy by stopping the barrel from moving as it heats up from shooting.
It's some of the best money you can spend on your mini. If you look at all the cuts and changes in the outside of the barrel, they all introduce stress into the metal as just making the barrel by hammer forging it.
Ruger does not stress relieve their barrels, so it really does a lot getting the barrel cryo treated.
It takes the stress out of the metal so that it does not bend towards the stressed part of the barrel. If any rifle needs cryo, it's the Mini.
#00 Below is really fast, 10 days at the most.