Hi Si
I used to use an Evolution keyboard with my computer some time ago and while not having the feel or robustness of more expensive keyboards, I never had any problems with it, but as ED says unless you can actually try it, you may get your fingers burnt.
The Evolution keyboards also came with a basic sequencer program, that contained the following edit functions, Track, Drum, Score, Mixer, Conductor, Event and Piano Roll, it could also import Wav audio files to mix with your Midi sequences.
In addition it also incorporates basic styles and an on screen keyboard, so was ideal to get you started. It used to be available on the Evolution web site but now seems to have disappeared, fortunately I still have a copy on my hard Disc, the size is 788Kb so if you have a broadband connection I could email it to you if the keyboard you purchase has not got any software with it, (It includes a quick start guide in the help menu) Don’t forget to Google as well.
Hope this helps.

Bill