If you're buying a PV kilt I'd recommend going with SWK as they actually make their own PV kilts.
The rest of the companies on your list buy them from Pakistani companies in bulk. However, I would recommend a deal that Scottishtartanstore have on at the moment. They'll make you a 5yard WOOL Irish kilt (with a choice of tartans with Irish connections) for only £120:
AND THEY DO HAVE SAFFRON AND A NICE IRISH GREEN AVAILABLE!

http://cgi.ebay.co.uk/IRISH-KILTS-5-...item3a5677f12c

P.S. I've been in both Scotland Kilt Company and Scottish Tartan Store's stock rooms to pick up some things and I can confirm that the majority of the stuff you order from Scottish Tartan Store will be Scottish-made and higher quality. Scottish Kilt Company's storeroom is just boxes full of imported goods. As far as I know the only Scottish thing that they stock is their white shirts.