I would buy a Samsung RF510, RF511 or RC530. These models are basically equal. Right now I'm using a Samsung Q530, and it's great. BUT, it does have a bit weak hardware...
RF511
Q530 is a model of 2010, and mine is running a Intel 330m CPU along with a Geforce 310m GPU and 4GB RAM. Since I'm also using a SSD I don't notice the lack of power, and it boots quickly, runs 1080p movies, is able to run basic games and do all the other browsing, etc.
Above all, I like it because it doesn't limit me like many other laptops do... It's running a BIOS and not UEFI, which means that I can install Linux with no problem, and I feel as free as I did when I was using a standard 30kg computer. Here I have roughly 1.5kg of tightly packed hardware, which enables me to do all the things I need!
Another great thing is that it was cheap, and that many of the components can easily be replaced. It can be disassembled easily by using only one screwdriver, and all the hardware can be found @ ebay or on Aliexpress. So it feels solid and reliable!
I'm not quite satisfied though, things could always be better... The RF511 I mentioned above would probably be an upgrade, and if I would ever buy a new laptop, that would be the one. Well... The other ones, RF510 and RC530 are just as good, a bit weaker, but the important thing is the ease of dissemblance and maintenance. If we look at Aliexpress, we can easily find a proper motherboard to upgrade both models:
This motherboard I find particularly interesting, because it has an integrated 420m GPU, along with a customizable CPU - meaning that you can buy any of the Socket G1 CPU's and install them yourself! Here's a guy who's running GTA 5 with a similar setup (although tweaked a bit):
The reason I wouldn't bother buying a more powerful motherboard with Geforce 540m and a better CPU (which fits the same laptop) is that it's utilizing things like Optimus, which basically is an advanced software for merging your integrated CPU graphics with the dedicated - I believe things like this typically causes more trouble than pleasure IMO, because things tends to become too advanced - making your CPU going haywire and the fan sudden accelerations...
Granted that I bought the motherboard I linked before, I would also buy the P6300 CPU, which is one of the weakest 2 cored CPU's of that socket - reason being that it would be enough, and it doesn't utilize any extremely advanced technologies like multithreading, which is reliable at this point, but still very advanced. Here's a brief overview of what I'm talking about:
https://web.stanford.edu/~ouster/cgi-bin/papers/threads.pdf
Running a P6300 would mean a 2.27GHz processor with a power 3x of what we had back in 2005, and that's not very long ago. Temperature would also be easy to handle, and if the need for a more powerful processor would arise, they are easily bought on Aliexpress.
After all, we spend lots of hours with computers, and therefore it makes sense to have a "setup" that is satisfying and comfortable. Too loud fans etc, can be detrimental to your work and your emotions, something worth taking into account.
My Q530 is still going strong, and while the Geforce 310m is only half as powerful as the 420m, it's still good enough for me right now. If I would ever buy a RF511, I imagine I would have a laptop good enough for of my needs, and the things I lack the most with my Q530 is USB2.0, but I think I'll survive.