I've got a level 70 rogue on ravenholdt. I've been using hemo as my main point-stacker and attack. I've talked with several rogues that own dope gear in my realm and none of them use hemo as their main attack.
The ones I've spoken with use Sinister Strike, but that eats up so much energy. Is SS greater than hemo? Hemo does 110% damage and is easy on energy, so It's easy to spam.
My rogue is pre WOTLK with full season 1 gear.