No downside imho. The crucial real ssd can push the new sata 3 (6gbs). And, more importantly it has proven that it requires the bandwidth in order to reach it's max potential. If, however, you do not have the capability than any other sandforce based drive will perform similarily. Ocz vertex II, corsair f series, gskill pheonix pro, etc.
The intel is simply not the best drive any more. It can compete admirably but the sandforce controller wins. Also, power consumption is so close that I can only see the difference in specs. Price compare the drives and pay close attention to the form factor. There are a number of 3.5" ssds now and they simply won't fit. Your laptop rocks. Add an ssd and you can push most desktops around. Batteries should last long time.