spikeair,
I'm still part-way through my training for the IMC but some of that has been in real IMC. The one thing that struck me is how much more difficult it gets when you're actually in cloud than when you're training in VMC with foggles on.
If you've not experienced real IMC in your training, I'd recommend trying it with an instructor. As soon as you get inside a convective cloud, it's suddently considerably bumpier and so you find yourself having to concentrate much more on just holding heading/altitude; forward planning gets very hard.
Losing that last tiny bit of visual reference out of the corner of your eye that you think you're not paying any attention to also makes a surprising amount of difference.
Mark