My feelings are that the best reasons to go DIY is for the fun of it. The worst reasons are because you started pricing components out and now are thinking "Well I can get the same parts as brand X for 1/20th the cost..."
If you aren’t really jazzed at building and learning along the way you are not going to be happy.
Having said that, Audiogon needs more actual builders and less arm-chair builders. The more people we have with hands on practical experience the better overall our hobby will be.
So, yes you absolutely can get into any particular type of speaker for a lot less than commercial speakers in many cases, but if you aren’t already thinking about what you want in a speaker made just for you I think you are missing out and always run the risk of building a speaker kit based on how much money you save.
I am a victim of this often. I see golf clubs which are $5,500 off for Labor Day and I immediately want to buy them. I don’t even golf. At all.
If you do want to investigate this further head on over to DIYaudio or the Parts Express forums where the hard core builders hang out.