The revision 4 looks different to the earlier ones, so either it isn't a revision 4, or the image on the OcUK product page is wrong.
See here, revision 3 on the left, revision 4 on the right:
http://prohardver.hu/dl/cnt/2013-07/99652/gigalap.jpg
If he gets a rev 3 he can just send it back under OcUK's 14 day return policy.
Apologies if I didn't make it clear earlier that it is only the revision 4 which has native support. I did mention that the revision 4 has native support but not that its the only revision.
As for whether Asus boards are better for the FX9370 or not, I can't really comment on that having never owned an FX-8 chip. I have owned several AM3 & AM3+ boards and CPU's in the past though.