Think it all comes down to if you are a DIY kind of person or not. As said, you will get much higher quality parts, at much lower prices, so if you are bargain type of person. Yeah, you can make a $10k speaker for around $4k. Yes, the resale will be less, but it started out as less.
Also when you DIY, you understand how it all work better, able to know what to upgrade, or change to get the sound you want. You can totally transform speakers with simple crossover changes.