They have the lowest fees, by far, in all of Canada with a fantastic $4.95/trade charge. Their fee is based on democratic pricing which just means that they charge 1 cent per share with a maximum charge of $9.95/trade. For most the $4.95 will be what is charged.
Outside of that fee there is nothing else charged. There are no inactivity, or administration fees levied against your account. You just make trades and profit -- can't get better than that!
I've been using Questrade for some time and there haven't been any problems at all. And if I've had questions there is a cute icon on the left (and sometimes on the right) of the screen that gives me direct access to Live Help Chat. Their support staff is knowledgeable and always eager to help.
Just the other day I made a large market order trade and the order went through with no fuss. I got a confirmation statement in my member's area and all is good in the world.
Look no further if you want a no nonsense discount broker with the cheapest prices there can be.