Nvidia is in a big heap of trouble right now regarding defective laptop GPUs. The 9500M uses the G84 core, which is one of the defective parts. You can't tell for sure if this laptop has one of the defective batches, but I wouldn't take the risk of buying any Nvidia mobile graphics at this moment.
More info about defective Nvidia parts here
The Radeon 3600 cards are not bad at all for mobile graphics. The upcoming 4600 will be kickass for mobile, but that won't be launched any time soon. If you're really desperate to have a 4670 in your laptop, then maybe we can work something out