I'm also seeing lots of cars for sale already built. Is the build experience mostly fun, or mostly pain in the a$$ work. Would you guys just buy one if you had to do it over?
The answer to your this questions is threefold, and depends upon - are you mechanically inclined, which manufacturer you select, and what personal satisfaction you want from the experience.
I have yearned for a Cobra since the 60's. When I decided to go for it friends said, "why not just buy one already built... that way you can just drive it." Personally, I wanted to build it myself. Now, I would know what I have, I don't have to fix someone else's mistakes/problems (I hate having to do that!), and their is one hell of a lot of pride when it is completed. On the flip-side, there are a lot of quality used Cobra's out there to be had if you are knowledgeable and know what to look for.
Would I do it again? In a heart beat! I had a blast! And I can say I built it - there's a lot to be said for that