As far as Storyline value goes, i'd take Triple H vs The Undertaker.. But if you wanna talk pure entertainment value, wrestling value, and all of the intangibles that go with it, i'll take HBK/Taker anyday.
Well you have the two past Royal Rumbles as backstory, and it all could come to a head at this years rumble. Imagine, HBK vs. Taker, WM 25 in Texas, that place is going to be insane.