If you've been holding back from buying an SSD, now is likely a good time to buy one.
The Extreme series is based on SandForce's SF2281 chipset, a proven performer. Custom firmware and the memory type used can change the performance of SSDs, even based on the same chipset, though; so while benchmarks are good, make sure to look at all your SSD options, first.
The prices themselves may be enough to convince, though: AU$129 for 120GB, AU$249 for 240GB and AU$489 for 480GB. That's a colossal drop for the 240GB and 480GB models, and although you still have to factor shipping into the equation, it makes for a very tempting offer.
A heads up: make sure to update your firmware once you get it, to fix an issue with TRIM.