My personal experiences (in brief)
I have been raised in a family that buys Macs as often as we can or need to (it's really great when both coincide...) That said, I love the portability of the 13.3 inch MacBook Pro, plus the ergonomics of the 13-incher in all areas work out better for me, because you're not supposed to type in such a way that the MacBook's edge is slicing your wrists. Then again, I type using the "hunt-and-peck" method and never could get the hang of touch typing.
With that said, I sincerely do applaud you if you can indeed buy a used/refurbished MacBook Pro Summer 2009 15.4 inch and it will work out for you. For me, as a college student, it worked out better to go to a real brick & mortar store and buy a new MacBook there.
I don't find the lack of a matte display option to be a deal-killer, and I wouldn't have bought any newer or older MacBook than this Pro from the Spring 2010 model line-up. I have both an Early 2008 iMac 2.8GHz Core 2 Duo 24-inch, with the (still awesome to me) 1920x1200 resolution screen, and my old used upon arrival 2.4GHz MacBook White Early 2008 spends its time attached to our bedroom HDTV, thus giving me a really good semi-desktop that can also moonlight as a really good (if not outstanding like the Pro) laptop. I keep it around because it's like a netbook or an iBook G4 in the Apple netbook role,but it runs Snow Leopard unlike the iBook G4, and Mac OS X updates won't shut it down like a PC netbook.
For my needs, I have three perfect placeholders (stadtholders in Dutch), and the MBP Spring 2010 13.3-inch 2.4GHz base model just has it all over both of the Summer 2009 13.3-inch models AND the Spring 2010 high-end model, which all the users and professionals both agree was the wrong choice.
Hope this helps and I am indeed new to this site!