If he is installing it in that 2008 Macbook Unibody 2.4 Ghz Core 2 Duo listed in his sig, then that is SATA-2 and there is probably little or no benefit in getting the 840 Pro. Right now the Samsung 840 120GB is $99 on amazon.com. If he wants to save some money, perhaps the Sandisk Ultra Plus for $89.
I think that Kingston V200 is an old model. Don't they have a V300 now?