At those price points why not use a laptop? I use a laptop and an external drive. That way I have two copies of each image. Also for me 250GB is too small.
Depending on what you need the laptop to do they can be pretty cheap.
I have been using a Hyperdrive Colorspace for a few years now. It has a decent screen and you can view jpegs as well as RAW files with it. I think mine is the 320GB model. It is about the same size as my iPhone. Very handy while traveling or shooting events.