Help needed ASAP for compressor choice (esp Spraycraft models)

Hi All

Can anyone advise me on buying my first compressor? I am a model maker who needs to spray occasionally. I would like the machine I buy to handle thick basecoats and primers, as well as fine details spraying. I already own a Badger Univerasal 200NH single action (but I may upgrade in time).

 I am currently looking at:

 The Axminster CP103 (link)

The Spraycraft GP (link)

The Spraycraft STD (link)

I don't really want to spend more than 200 GBP.

The thing that is confusing me is why there is such a price difference between the two Spraycraft models as their spec looks very similar. 

Any thoughts???