@Ichigo Knight, I would save up for the tri-top. You could try the elastic method - making SURE to bind in a K-pattern, not just "around". This is very important for proportionally large or firm breasts - otherwise you're constricting your rib-cage too much to get the pressure needed.
But for how much that will cost you and how annoying it is to make, you might consider saving up.
@shattered-vase, I have asthma and use the tri-top. T-Kingdom is overpriced and not nearly as effective, and only works well on breasts that don't require much pressure to bind.
@Axelai, the right size will make a huge difference. I've tried on a friend's binder that was too big and it just hung off me - the one in my size is completely different and works.
I would get the tri-top. It's the most effective binder on the market, that I've found. I'd love to know more about the one you've linked to - but it's much more expensive than the tri-top, which is PROVEN to work on large and firm breasts. Just make sure you measure the right way - over fullest part of bust added to the measure of your rib-cage under your breasts divided by two.