I have always thought of the National Trust as 'Upper Class' and English Heritage as 'working class' if you know what I mean. I have always found the staff very friendly and helpful at both organisations it's just that the prices for the National Trust properties are much, much more expensive than that of the equivalent places that English Heritage manage.
Not only is the English Heritage Membership cheaper than the NT but I can take up to 6 children that are members of my family (I have no children so take my nieces and nephew with me to lots of places) with me on my visits and they get in Free as part of my membership.
I've never fully understood why indoor photography was banned at all properties, it just doesn't make any sense and just adds to their reputation as being snobbish. I can understand why flash photography would be banned as it can help protect paintings and the like.
Out of all the EH places I have visited (from Charles Darwins 'Down House' to Boscobel House & The Royal Oak) I have been able to take photos in all of them (there was one place I couldnt take indoor photos but I cant remember where that was).
I'm a little surprised EH let the NT ban indoor photography in some of their properties as EH give the NT quite a substantial amount of money in the form of grants etc.
Still no reply from the email I sent the NT, I guess they are being careful with their reply!