So I've tried two of the three contenders.
FOXIT PHANTOM PDF BUSINESS (US $129):
Works great, generally Easy to use UI seems designed in a recognisable, familiar way had a problem when rotating / combining larger PDF (scans: 300dpi A0) files, 5 to 7 pages at a time, software kept on crashing, worked fine on smaller files though cannot zoom in on PDF with mouse scroll wheel couldn't drag&drop multiple files into the UI area to add them when combining PDF's fair price but will have to live with some irritations.BLUEBEAM REVUCAD (US $299):
Works great Fairly easy to use the UI will take some getting used to, could do with better organisation didn't have a problem when combining and rotating multiple PDF (scans: 300dpi A0) files, 5 to 7 pages at a time, even not so when combining 39 page 300dpi A0 pages, was quite snappy about it actually (I'm quite impressed) did I mention expensive? This is the only thing actually keeping me from purchasing this product.