A good working rule: take any advice Pipeline gives pretty seriously.
But my take: Great drum tracks have been historically recorded with pairs of either of those mics, so I would base my decision on the consideration of what other mics you already own.
If you already have some other good quality large diaphragms, i might lean towards getting the 451's. That way, if you need some small diaphragms for other applications (when they aren't being used as overheads) like on an acoustic guitar, piano, percussion overdubs, etc you'll have them. I'm assuming this might be the case, because if you already had better small diaphragms, (like Oktava MC012's) you probably wouldn't be using the BG's as overheads.
Since the 451's are cheaper than the 414's, even if you don't have a good large diaphragm for use on vocals, etc. you'll almost have enough via the price difference to get one decent quality LD for vocals, etc. (KSM27, Baby Bottle, or something Chinese).
