Well this is a whole different ballpark then
I'll spare you my usual sermon on the avaiablity of cheap, good guitars (like £300-400 cheap), suffice to say that variations in wood quality and manufacturing tolerances mean they can be found quite easily, but buy the guitar you play - dont get the same model off the net. If you like the very guitar youre testing, buy that guitar, one of the same model may well not (indeed probably wont) be the same. Sometimes the variation is quite remarkable, in tone and quality.
On the other side of that coin, you mention caparison - I've only played one, but from its build quality and acoustic performance, its £1500 tag was an insult - I wouldnt have paid 300 for it; I've played pacifica 112s that were better performers.
Jackson pros - I have had a pro series jackson (albiet the top end pro of the time - a DX1) for about 10 years now and its a great guitar, still in my top tier. They can be very good. With a gotoh trem and c-bomb and trillogies mine slays. That said I recently had a pro series in for work (dont know the exact model, but it was a 2hb dinky that apparently cost about 450) that was absolutely spot on except for a lump in the board on the plain side from about 17th to 24th where it wasnt planed correctly that forced the guitar to have 2.5mm action or higher on the high E! It was the only flaw with the guitar, but its a big flaw (corrected by lowering those frets so they were level even if the board wasnt). This is one of many experiences that reinforces my "Any brand or model can be a jem or lemon, buy the guitar you play" mantra.