Please note that the price of SBD is about 20% lower on Bittrex right now compared to Poloniex. I would say this is due to the fact that you can't transfer SBD to Poloniex right now so everyone is selling their SBD from Steemit through Bittrex.
It might be an idea to power up with your Steem Dollars rather than taking a much lower price on Bittrex. Although, the price is still higher than $ so 50/50 is a better payout option.
The volume on Poloniex is far higher so I would say that price will revert closer to the Poloniex price once the deposit facility is enabled again.