I don't see the point in buying part worn tyres [no matter how good they are or how reputable a source they come from] when budgets are probably a few pound different.

It's a false economy anyway imo. By the time you've knocked a couple of sets of part worns out you could have bought a DECENT set in the first place that would probably have lasted as long.

As said above, the tyre is the only contact you have with the road so penny pinching is ridiculous.