Pretty good fun, both single and in groups. Bit short though.
Only 4 courses and 3 weapons do limit the fun a bit and I suspect you'd get bored of it after a few weeks. However, you'll almost certainly come back to it after a few weeks break as its simply good fun.
Hopefully Sony will add a few more levels in a FREE download in the future.
Overall, not a bad £3.99 (or how ever much it was, I forget now!) to spend on a game