nikon 5100 hdr mode

Looking at buying either a canon 600d or a nikon 5100. this will be my first digital slr (i used to use film slr's about 15 years ago) I have been and had a good look and feel of both, on a couple of occasions.
They both seem to be fantastic cameras. I prefered the feel of the canon in my hands but only a tad.
As i shoot a lot of landscapes one thing that did appeal to me was the HDR mode on the nikon. On my present camera i always have under expose all my shots in order not to wash out the sky highlights, then correct the landscape later on. On the other hand a dont want to pick the wrong camera on something that might only be a gimmick that doesn't work very well.

I am aware that i can achive the same results by doing the job propally with either graduated filters or bracketing, but i'm often on 15mile ridge walks and just want to fire off a few shots quickish

One other question is either the canon or nikon slightly more weather proof.
Thanks for any advice

I have a D5100 and I tried the HDR. (At least I think that's what I tried.)

I expected the camera to take a single frame or a set of frames and combine them into a single shot.

Nooo, that's too straightforward.

It took three successive single shots (requiring three successive shutter button presses) at various exposure values.

Of course, not knowing this, I ended up with a third of my snaps overexposed, a third underexposed and a third at standard exposure (normal dynamic range).

It seems that "HDR" on the D5100 is best used with a tripod ( to maintain frame registration in post processing) and, ideally, with a remote control.

The camera, it seems, does not perform the necessary post processing of the shots but just gives you a series of shots with which you can tinker.

If a more experienced user of the D5100 has had a different experience please tell me how to get true HDR shots in-camera.