I didn't see it last week for £300, but the point is a price increase of 16.6% in one week sounds like hyperinflation to me, regardless of how good an amp Alfie thinks it is.
It's not a bad amp by any means, but it's not up there with hard-wired, point to point amps with heavyweight transformers. Judging by the chorus of voices proclaiming it as the bargain of the year at £350, all I can say is, why don't you buy it then?