OP, the 6ppc Sako rifles will usually shoot extremely well, with a little effort put into load development, accompanied with decent glass.
The felt recoil of the cartridge is similar to a 223rem and it's capable of taking any game the 223rem with similar weight bullets.
As guntech states, that 1-12 twist rate is a detriment, but with good bullets it's a great cartridge for Coyotes and similar size animals.
Most of the early 6.5PPC rifles wore 1-14 barrels, as the cartridge was purpose designed for match shooting with lighter bullets, with flat bases and J4 jackets.
When Sako came into the market with the 1-12 twist in a commercial, off the shelf rifle, things changed a lot, because the tighter twist enabled use of bullets up to 85 grains.
Most loading tables show loads that were similar to those used by match shooters. The PPC case is quite strong, and capable, IMHO, of higher pressures, up to 60,000psi. This might allow use of bullets as heavy as 90 grains, as long as they aren't the long, streamlined ELD or monometal types.
If you are a Varmint hunter, you may want to rethink your interest in the 6PPC.
If you can't get your head around the 6PPC, which definitely isn't everyone's cup of tea, your options in that rifle will be limited to magazine length, and rebarreling.
I no longer shoot a 6PPC, but not because I didn't like or appreciate the cartridge or the rifles I had it chambered in.
The twist rate is, IMHO, not that big of an issue, simply because the case capacity is limited and lighter bullets would be best suited.
