I wouldn't get too hung up on how long it takes to get confirmations. The important thing is being able to place orders quickly and have them appear in the queue quickly so there is no delay in execution. If you can see your trade has gone through and if the order has disappeared from your open orders list and the stock has appeared on your holdings (for a buy) or disappeared (for a sell), then you know it's been executed. So if it takes a while before you get the contract note, that really doesn't matter. imo. I don't use commsec but my broker can sometimes take a very long while (several hours but generally quicker) to email confirmations out but the order placement is pretty much instantaneous on most occasions. Not sure if that helps.
