I guess from my experience internals give you information, and I'm a bit pressed to see how getting information is a bad thing. A lot of discussion here has been about being disappointed. I find this point a bit weird....I do lots of things to find out more information. When I had high blood pressure during pregnancy I had urine and blood tests, and I was very disappointed with the results. But I'm a big girl, I dealt with it, I much preferred to know and be disappointed than not know. If you are in a similar frame of mind I don't see why it should be a problem.
So with my situation, I was in labour and had an internal at about 2:30am and was 2-3cms. At about 3:30am I opted for some pain relief (epi) as I was not coping and I was likely to be in labour for a long time yet. An internal at 4am revealed I was 10cm. The point being it I had of had an internal and got the information about how my labour was going at 3:30 I would have not had an epi at that point in time. I thought what I was feeling was 2-3cm type pain and there was no way that I could see myself doing that for several more hours, when what I was experiencing was actually transition and something I could have dealt with if I had of known pushing could be a few minutes away.
I think you've hit the nail on the head with the midwife vs. ob point, I think your midwife friends are taking the context they want to from your situation to push their own agenda and ignoring the facts i.e. you requested it and are happy for it to occur. I have absolutely no problem with some one giving me information about my options but if in the process they are being unsupportive and unhelpful - well that's not helping me and I'm probably not going to be as receptive to their point of view.