Wow lotsa questions, First of all i have less than 300.00 into any one of em, and thats including NEW parts. I have 3 different ones that i own, by different i mean 1 target, 1 wall hanger (ill try post pic) and one knock around, ie: carry, can get scratched etc. Also the last one is set up for the 400 Cor-bon conversion which i have a separate slide and bbl for. Thats one HOT round.
There are No difficult parts to install that i found, however there are some parts that need to be installed correctly, ie disconnector sear trigger set. That can be a little trickey. All in all it was fun and productive. The two that i dont own were parts kits that i helped 2 of my friends assemble. A little tweeking tuning polishing etc and 99.9 % reliable.