Mavericks is slow with 2GB of RAM using Xcode 5, should I upgrade to 4GB or 8GB? I have a 13 inch MacBook Pro from mid 2009 (5,5). It's really slow when I switch applications, I'm using Google Chrome, Xcode 5 (I already disabled "show live issues"), and not many other apps: Cog (simple audio player) and f.lux and the Terminal.

Right clicking often takes 5 sec, creating a new Finder window around 3 sec.

I'm just asking if 4GB will really be enough since I use Xcode to compile a C++ project, or if I should get 8GB. I'm not very concerned about battery life, I'm just worried that 4GB would not be enough to be comfortable, OS X seems to use a lot of memory.

I'm just wondering what are the best websites to buy memory that is compatible with my Mac. I've looked at macway but it seems they don't have RAM for my model. I don't think I'll buy from OWC, it seems very expensive... Corsair also seems to make RAM for Macs.

I'm also ready to buy good performing RAM, I don't know if there are better performing RAM out there, or if a 2009 MacBook would really benefit from it.

Any advice?

I also tried to check my page out value, could not find it in the new activity monitor, here is the memory thing anyways.
8Gb would be best if you can afford it. I've always used crucial.com for RAM and had no problems.

An SSD drive would also really speed up system performance.