I just got through building my own set.. I had a similiar mind set as you prior to building my set. Cutting, cleaning and welding aluminum is difficult and time consuming. For the 530's with the Tubes is a real chore. I agree they are very expensive, but in hind site, I can see why the cost is so high. My 2 speakers took probably 30-40 man hours(2 people, one working about 16 hours the other 24) I'm sure you could get that number down.. but it still takes a lot of work.
It also depends what you are wanting to do.. a single can is pretty easy.. but a connected set of cans makes for quite a bit more work.