I would try the Eagle boss first. When/if you are able to start doing timed runs for bear mounts, you'll want to do Eagle -> Bear -> Dragonhawk -> Lynx anyway.

Eagle boss is more of a DPS race; Bear boss is a tank check. I've had the nost luck with me (paladin tank) tanking bear boss in normal form and Druid tank taking bear phase.

If your DPS is your strength, try Eagle boss.