The only benefits I can think of for having a solid state drive are:
- Faster booting, and application loading.
- Longer running time.
- Less prone to shock damage.
Well...
- I rarely shut my MacBook Pro down, if ever. I simply close the lid, in which case the machine is ready to go in a few seconds, so a faster boot up time is not really going to be much of a benefit. Most of the applications I use are already loaded as well, so no real gain there either.
- My elderly MacBook Pro runs for quite long enough for one sitting, 2 to 3 hours, it will play music with the screen blanked for over 5 hours. Even on the longest flight I wouldn't use it continuously anyway. Travel power adapters help anyway.
- I try to protect the whole machine from shock damage anyway. So a rugged drive is of no benefit, especially considering I keep a Time Capsule backup anyway at home, and replacing a drive is an easy job.
The price differentials between solid state and mechanical hard drives is so wide the strongest argument has to be on cost at the moment. A mechanical laptop drive is about 10GB/£ at the moment, whereas solid state is only 0.5GB/£, and to be honest I prefer having the space rather than any potential performance boost.