Thanks!  That is what I'm hearing  on the Timberwolf frame, I appreciate your first hand knowledge. 

Now to find a PF45 review.  I'd love to do the whole thing myself, but if it comes down to a less than stellar final result I'll just skip it.

I've decided to put together a complete glock style 10mm build.  Needing some recommendations on the frames from anybody that has ACTUAL experience with either platform.

Polymer80 PF45 frame: I like that it's an 80% build.  I've read some reviews that question the rear slide rails as being plastic instead of metal.  Is that accurate?

Timberwolf seems to get good reviews, but is a "firearm" and requires an FFL, adding cost. 

I've already got a KKM 6" barrel on its way. 

Also, any slide source recommendations? 

I've recently nabbed a G20C, that was purchased as a backcountry backpacking sidearm.  I've read all about the needs for tuning it to deal with full power/heavy loads.  My plan for the gun is to carry it at the end of August on a 6 day backpacking trip, loaded with 200grain underwood.

So with all that being said, it appears that a 20-22 lbs spring will be the ticket from what I've read. I'm planning to order ammo and and spring assembly tomorrow, so that I can get plenty of time and practice with it. Anybody have any feedback that would lead me away from that?  Looking at this:

https://www.midwayusa.com/product/3415156761/wolff-recoil-spring-glock-17-20-21-22-24

I'll be picking up a G20C from a good friend of mine here shortly. He bought it New several years  ago and has only shot it a handful of times.  I've been after him for a while to let me take it off his hands.  I intend to use it as my out west backpacking sidearm and also anything that calls for  open carry such as hunting, 4 wheeling, etc.  I look forward to digging into the data you guys have.  I've been reloading for my G23 for several years, so it won't be long before I start to home brew for this one as well.