Nice collection. I agree the 300s is in a different class to most new spring rifles. Nice to see a theme in the collection.
I am also going down the collecting the Feinwerkbau line of stuff at the moment. I bought three 300s models with a couple of months of each other (No idea why, but I'm pleased I did now). I have been spending my time restoring them to as as near as new condition as I could reasonably get them. All three are now reblued by Shaun of ISP. I've stripped and restored all three stocks and put new springs and seals in them all. They pretty much all look like new now.
I think my oldest one is around 1974 Serial Number 137xxx.
More here :- http://www.cones-stuff.co.uk/Feinwerkbau%20300s.htm
Then I started on the pistols. I have a Model 65 that is in very good condition, so no chance of me taking that one apart. The Model 90 is in good nick as well. My C10 CO2 is a little worn in places and the latest one a Model 103 is like new in the original case.
Thanks
Mark