cosic cube sayeth:
<<Do you have anything to attest to Doomsday's alleged "equal to Flash" speed?>>
nothing beyond blue beetles word in JLA #69 where he states doomsday is faster than flash. doesn't completely make sense though, but i suspect he meant his reaction time and his ability to strike at super speeds which supes commented on several times. also, during the battle, it was believed by superman that doomsday continued to get stronger - likely because we now know he adapts to attackers. i suspect if he fought hulk, he would adapt to meet hulk's growing strength, and if he fought both hulk and juggs, he would adapt to meet them both. forgetting that, he'd already adapted well beyond supes, so that puts him above juggs and anything but a mindless, fully savage hulk. but as hulk grew in strength, dd could conceiveably do likewise.
it has been established in books that both hulk and juggs can be put out by enough force. dd HAS that force, and if he doesn't at the start, he will have it by the end.
ps- saying dd was beaten by imperiex is like trashing thor for getting whooped by a full power galactus. different orders of magnitude - AND we still don't know if dd will come back from that disintegration.