I have opted to pay above cover price just one time for a hardcover. It was for X-Force/Cable: Messiah War at close to $20 over the original cover price of $40, so not too bad of a price hike.

The only elusive/hard to find book left on my want list is War of Kings. It's the only hardcover from the Abnett and Lanning cosmic era that I do not own but prices online go way too high for me to bite.

And as someone that owns a copy of the Battle Chasers hardcover mentioned in the OP I am so very glad I bought it for $60 when it was first available on Instocktrades years ago.