Don't go with Natwest. I've just had a nightmare with them due to me purchasing a car and moving house at the same time. Obviously with a finance deal I needed proof of address.
I went into the branch to change my address. I was told that this would take a week. I called Natwest after 5 days and it hadn't changed. The guy I spoke to on the phone said that this was something he could change immediately though... So that was 5 days wasted.
I then had to request a statement showing my address on it as I didn't have any. This cost me £5 and I was told would take 5-6 working days. OK I thought, not ideal but at least then things will move along. On the 5th day, no statement received. I called them asking why and they said that I should wait until the 6th. I did, no statement. Called them again and they said "Oh, the statement takes 10 working days to come". At this point I lost my temper with them as 10 working days would have taken me to the end of the month anyway when I would have received a statement for free, so I wouldn't have agreed to it in the first place. I got my £5 which was at least something.
On the 8th day I had a statement come through the post. It didn't have an address on. So I've been sat around waiting for Natwest to send me a piece of paper with my proof of address on and STILL haven't had it. Meanwhile BMW have been able to service the car, clean the car, and prepare it for me to pick it up.
My parents also had major problems with Natwest and have since changed to HSBC and had no problems. I have also now changed to HSBC and can't wait to close my Natwest account.
Obviously some people will say that Natwest have done them no wrong. I was one of these people but then realised the only reason I'd never had a problem with them was because I'd never needed them to do anything for me before.
Good luck with whatever choice you make.