Not sure why it would be cheaper to let Apple do the upgrade. What you get for that price is less than what you could do yourself in a snap.
If you want, I could do a small review on daily usage of the coming Vertex 3, which supposedly should be the fastest thing around (atleast until OWC and Crucial spit something new out in a couple of months). I'll be getting it in 2 weeks time, and very much looking forward to it.
The price I'm paying for the Vertex 3 is $65 more than the Apple SSD of the same size (256gb). The speed difference is significantly more...
The advantages? Well... I'm not hardware buff, but I did read a lot before making up my mind.
Depending on what your needs are, you should find out what the specific drive is good at. I absolutely need one that is good at both random and sequential read/writing. That's why I chose Vertex 3.
If I only needed random writing I would choose something else (cheaper).
Also note the talks around how some drives seem to be causing problems for some machines. I noticed a lot of Intel 510 talk, and that coupled with its extremely inferior speed I chose not to even take an interest in it.
What you'll be getting is speed, less heat and no moving parts... moving parts are bad 😛
What will you be using your computer for?