I took a look at the swap stats and didn't see lots of ins/outs, so don't think adding an extra .5GB RAM will help all that much.
The less ram a Macintosh computer has...the faster the swap file & page outs grow. And grow to a point that the computer starts to slow down. So the more ram a Macintosh computer has...the longer a user can go between rebooting.
In my experience (which is fairly extensive)...this "rule" holds true for up to about 8gig of ram. For me...I have three laptops I use regularly. Two have 4gig of ram...and one has 8gig of ram. The two with 4gig of ram I need to reboot weekly because of the swap file and page out sizes. The one with 8gig of ram much less.
In your case (or friends case)...going from 1.5gig of ram to the max. of 2gig of ram is a 33% increase. Certainly not a small amount.
I only thought of the SSD as a relatively inexpensive upgrade that will cut down the boot/load time a tad. I don't think he's really in the market to get a new laptop (not a real techy person).
But getting the SSD doesn't sound like a bad idea, assuming focus is minimal cost to stretch out life?
Although $120 may not be a lot of money to your friend (which is great)!
This computer is probably worth about $300-$350. So a $120 investment into it (or more) is a pretty significant proportion of it's total value. This is why I say...sell it...add the $120 for the SSD upgrade + some additional cash...and your friend could have $500-$600 for a newer MacBook Pro.
Believe me. With $500-$600 to spend...a MUCH better used MacBook Pro can be purchased.
There's nothing "techy" about this...it's all about speed! And speed seems to be exactly why this SSD upgrade is being considered.
- Nick