This is not a good deal. The Sony made NBA 0X basketball games are terrible. Even worse than EA's NBA Live series.
You are much better off paying the extra $30 to get NBA 2K9 by 2K Sports which is the only decent basketball sim available.
The demos for both NBA 09 and NBA Live 09 are available on the PSN network if you want to try them out beforehand.
But keep in mind, I usually don't buy sports games, or if I do I don't until they hit a price drop because sports titles become obsolete after every year. Just my opinion of course.