I wouldn't touch an HP, Toshiba, Dell...those things are overpriced or just carp. Asus is a really good company and generally make superior product for any price point. If you are buying a desktop, buy Asus motherboard.
Asus laptops are good for the price point but are not the easiest things to repair if you have problems.
Almost all the laptops/brands are coming off the exact same lines, with the same components. One day the line will build Dell, the next, someone else. It really comes down to the motherboard and its design and how much the brand is willing to pay to put it together.
We have been buying Acer laptops for at least 10 years. Not sure how many that is but enough to say with all those purchased we have had hardware problems with less than 1% of them (2 out of hundreds and hundreds...one Acer even covered out of warranty...we had to go through their wholesale channel to get to their service people). Acer's have been rock solid for us.
Acers also have very little bloatware (like HP, Compaq, Dell, Toshiba...) so your computer won't have a bunch of carp running in the background.
Get a third generation Core i3 processor (can't remember the product numbers) for general. For graphics, get a Core i5. If you need heavy duty processing, Core i7 (I think this will be out of your price range). Going up in the processor capability chews battery life.
Stick with an Intel Core series processor and avoid AMDs. AMDs are cheaper for a reason. The processor chip or motherboard (or both) burn up a lot...for every brand.
If you need graphics, look for something with a separate video/graphics card and at least 4GB of RAM on the motherboard.
Get something that has USB 3 built into it.
If you can still find one with Windows 7, get it. Avoid Win8. I am still not that thrilled with Windows 64 bit architecture, yet. Their are still some hardware glitches and some internet stuff may or may not work with 64 bit. We generally reload Windows in 32 bit (keycodes work for both 32 and 64 bit versions). For almost all users, their is very little gained by the 64 bit, other than more than 3GB of RAM.
Acers also have very little bloatware (unlike HP, Compaq, Dell, Toshiba...) so your computer won't have a bunch of carp running in the background.
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