what to buy: hybrid or mountain bike?
I'm going to be buying my first bike in prep for a 105km race here in Cape Town, South Africa. I have to decide between a mountain and a hybrid bike. I was thinking hybrid as I'll mostly be doing road, though would like to be able to go on gravel roads (am not going to be riding on mountain paths!). But I've been told (at a local bike shop) that they don't recommend hybrids as the full road-bike sized wheel is dangerous off-road as one has a lot less control...
So if my use is going to be 20% off road and 80% on, and I'm not a dare-devil, how worried to I need to be about that big wheel? thanks!