anyone seen a Netsuite Bill Capture in action ?

No, but when I inquired about it with my account rep, he was like "It's US-only, small volume only. It's not ready for you guys yet". We use Concur's Bill Capture feature currently. When the sales people are trying to not sell you stuff, that's always a troubling sign. So just be aware it's a capability they're still actively building out, I guess.

Thanks for feedback I also asked our AM here in UK and first thing he asked me was : Do you use SuiteTax or legacy one ? ..... For bills processing we use ZoneCapture from Zone&Co (previously FastFour). Works well, but not free obviously.

I did see a demo couple of month ago, in my opinion it is still a premature product compare to others products. I have used Tipalti, Avidxchange, Mineraltree and Stampli in the past, so I am quite exposed to OCR and AP automation.