Acer is crap.
HP is meh, they don't seem to have been built with quality (cheap plastics...) and a lot of people complain about their HP overheating after some years.
Samsung has the same quality cheapness as HP.
AlienWare is good but way overpriced for what they offer.
Dell seems great, according to the internet.
Asus is great. I've had one since last year and damn it is good. Good quality build, made of aluminium, last long, don't overheat even while playing video games (unfortunately some Asus software crap is pre-installed...). The Internet says it's one of the most reliable with dell. Unfortunately their costumer support is so shit even shit tastes better.
Lenovo is apparently pretty good too.
Now every laptop serie is different, but this seems to be the general consensus.
If you need one for uni I suggest you to buy a light one (if you need to bring it to lectures and travel a lot with it like I do). An ultrabook is really awesome for uni tasking. Ultrabooks are usually 21 mm thick (0.8inch), have an SSD with Windows installed on it for quick startups and weight 1.3kg (2.90 lb) or more, usually the maximum is 1.8kg (4 lb), battery included. Battery life is 4-5 hours minimum and a maximum of 9 hours (depending on what you do with it), mine used to last 5 hours on plane mode while using Word.
Mine can run CSS, Gmod, L4D2, TF2, Warthunder... on high quality with just an i5 1.7gh (can go up to 2.5 something when needed) and a nvidia 635m. I suggest you not to buy an i7 as it eats your battery more and maybe a slighty better graphic card. But eh, that depends on how much you want to put in your laptop. Mine costed 950 dollars (700 euros, 560 pounds) a bit more than a year ago.