One Buckeye amp on the vertical.The reason audiophiles put their stuff on the floor is because they can't find audiophile grade duct tape to stick it to the ceiling. Which reminds me I need to patent cryogenically frozen duct tape and sell it for $500 bucks a roll.
Ironically they like to elevate their speaker cables *off* the floor made with audiophile grade wood. Reminds me of being a kid and running those bright orange hot wheels tracks all over the basement floor.
On a semi serious note, why do we keep our AV gear Horizontal? One thing I learned in data centers over the years and seeing a lot of expensive stuff over heat and cause data loss is large circuit boards last longer in a vertical position. Why? Convection. All my AV stuff is kept vertical no matter how goofy it looks. I've never had an amp or receiver or separate go bad. Maybe its luck, but all my audio buddies who shove their gear on tight horizontal av shelves end up griping about problems down the road. I wouldn't keep a 2U server housed like that without active cooling.
Edit-note to self-must dust more often behind tv...