boxes strewn on the floor?Voting options should include "It depends"?
:^)
No manufacturer can be all things to all people but there could be more DIY options given that these will be "kits". If Mr. Thiel does go outboard it would probably not be too onerous for a DIYer to modify these with binding posts and simply run a speaker cable from the XO on your rack to the speaker.
For myself, I prefer a solution of a high-quality strap from the external to the speaker cabinet (XO cabinet on the floor directly behind the speaker) and then cabling to the amp as normal.