Nobody else responded so I'll bite.
Man, this would make me really uneasy. I think I would probably say no. The contract is just too long for someone that is clearly in decline to me. You say the 4th year is non-guaranteed, but you're still on the hook for most of it anyways and if the Bucks realize their potential with Horford, the entire thing is guaranteed ($14.5 mil guaranteed regardless, $19.5 mil guaranteed if we reach the finals at any point, and fully guaranteed if we win the title at any point).
Might depend on the pick I guess but I'm not really interested in Horford.
Never mind, I completely botched his contract. I thought 4/$97 was the maximum amount and that could be further reduced by not guaranteeing the last year, but 4/$97 is the already-reduced amount, so basically it would be 3/$97m. Hard to see that working for assets and salary except as a part of a multi-team blockbuster but I do think he would be an upgrade over Brook. Just better intangibles and mobility and versatility.