4520s - poor battery life and difficult to use the integrated mouse, poor battery life
5320m - discontinued model?
6560b - poor screen resolution and graphics.
I have also been looking at Lenova and they seem to have some good models.
I guess the issue is there are too many laptops to choose from and obvious particular outlets will promote their stock as being the best.
I travel a lot so portability is essential as is battery life, but it must be perform well so looking i7 processor and 4Gb Ram.