I enjoyed assembling, touching up the few parts for perfect fit, and most of all finishing the metal and wood. I did a SMR, and there were parts that would not fit if you didn't do some chiseling, like the buttplate and the ramrod entry pipe. Both took me several hours over several days to get just right. Then I decided to add a toeplate, cutting one out of an old antique tool. Worked on filing that down and fitting for several hours over several days, again to try to get it just right.
Yes, you are basically buying a rifle that needs some fine tuning on the assembly, then finishing. Like the plastic ship and plane and tank models people built when I was young, you could tell one that someone slapped together. Parts with large gaps, glue everywhere, things out of line, ....shoddy work can be done by anyone in a hurry. I went slow and enjoyed the process and again, that is mostly in the finishing. The most fun part of wood work to me.
There seems to be a couple of people who refuse to think this type of purchase is worthy. Their attitude smells of snooty elitism and "I'm better than you because I do something you can't." Well, every one of us is good at some things, and bad at some things. I'm sure I'm better at a lot of things (like systems engineering, training fighter pilots, etc), more than spending years learning to build a rifle from a plank of wood, casting or forging my own parts, and using only 150 year old chisels and no sandpaper. Cronies in many hobbies (sorry, this is not a lifestyle for me) drive out newbies with their arrogance and looking down their noses at anything different. THAT is why so many hobbies have died on the vine the past 30 years. It saddens me, because I too remember the Buckskinner days of the 70s.