DIY. Whose speakers would you use?

Orpheus 10, I have heard the Polk's are good sounding speakers for the money. So are Paradigm and others.

The Audio Note kit is primarily for those wanting to use relatively low power tube amps, or maybe low power SS Class A amps, so a different market.

Regarding quality, you should check out the website and detailed manual and build link. These kits are already designed and, if you purchase their cabinets (a no-brainer for $950) then all you have to do is assemble - much different than starting from scratch.
Audio Note Speaker Kit 4

BTW - have you ever looked inside of a manufactured speaker, just parts and wires, cabinet work and maybe some damping material. Other than a few who use high end cabinet materials like Wilson, Hanson, and some others, most are rather ordinary. In addition to using high quality drivers and parts, what makes a good speaker is the crossover/driver/cabinet design, and component matching, all of which are already done with the Audio Note kit. In this case, the kit would be an alternative for those considering purchasing one of their very similar manufactured products costing double or more.

Not really only answers why you would not want a kit not why it would offer less performance or be engineered to a lesser degree. Most a kit wouldn't even be a option but there are some very well thought out and designed kits available most are not so costly. And many kits are a very easy build. Like SEA X-1 kit from madisound.

If I were to build a speaker, I would use a Heil Air Motion tweeter, a Vifa midrange, and a 12" neodymium woofer. The crossover would be a 3-way, 4th order, T-type. Crossover frequencies would be 400/2500, 94DB efficiency.

Capacitors for the midrange and tweeter would be Jentzen Superior Series Z-caps,and Solen Metallized Polypropelene for the woofer, which would be side firing.

A zebra wood finish and the project is complete.

If I were seriously looking for a recommendation for a kit, Audiogon would not be where I would ask this question. Some of the posts on this thread are excellent examples of why I say this. A lot of opinions from some who probably don't know which end of a screw driver to hold.

An interesting assembly Orpheus10. The finish would not be my taste, but otherwise, not bad at all.