On IB it works fine.
However, the delay with short sale is usually the short sale rule, not the broker [although 10 minutes is a lot, I hope the stock was very illiquid and explains it].
It depends also what kind of limit you set to the order. On IB and NYSE, if the stock is liquid, I put in a market order for the short. I noticed market orders are faster and do have price improvement if the size is not too big.
No market orders in illiquid stock or Naz for me.
In a tanking stock, the uptick rule can put you on hold for a while. Well.. it does mean you come for the shorting too late ! Uptick rule sucks.