Message to User:
You used parentheses in your post, so I know your shift key isn't broken. Well, unless of course it only works on those two keys, but I'll just assume that isn't the case and give you an infraction for being plain old lazy.
i really dislike fights that are stack friendly and vashj is definitely one of them.
bring a bunch of range dps and profit.
4 hunters makes this boss really easy, lot of melee dps makes it very difficult. in t4/5 gear, a hunter can take a cardinal direction stairway alone, whereas it'll take 2 melees to keep it clear. you also need at least 5 range dps killing striders (not including the kiter)
melee are also vulnerable in p3 when she is rooting a lot on top of goo, not to mention any time any melee gets static they're going to automatically generate at least a couple seconds of raid damage. this isn't an issue for range. again a couple hunters killing sporebats in p3 will make this a lot easier.
imo, vashj >> kael (especially now, but before as well)