Had a 5742Z with pentium processor, 4Gb RAM and 500Gb drive for about 4 months now. Can't fault it, it is quite light, the screen is excellent, keyboard feels nice, performance is very good. Delivery from Amazon was very quick, set up was totally straightforward, though I would recommend removal of most of the OEM trial software, but that is true across all manufacturers. Wouldn't mind an extra USB port or two on the back. I don't use it on battery very often but it seems good for well over two hours, though this will deteriorate over time.
All in, an excellent vfm machine, and build quality is excellent despite what some negative reviews say (be aware some negative Acer reviews are spammed across several products and do not refer to the products they are listed under, but products several years old and should be ignored), in fact sturdier than the last few Dell laptops I have had. Acer will certainly be near the top of my list in a couple of years when it comes up for replacement