Thanks all for your replies!
Now that I think about it, it is a rather difficult question which depends on a lot of variables (it's always silly to post a thread just before you go to bed right?

). The area of the route I'm trying to make is in the Great Lakes area of North America and I'm at the point where I'm adding eye candy to the route (like bridges, tracks, sidings, etc...). From my experiences in train travel (mostly going from Montreal to Toronto or taking a commuter train into Toronto) most crossings were indeed level crossings with a few underpasses and a lot more overpasses. I found rural routes used grade crossings/overpasses more while urban routes tended to use a mix of underpasses and overpasses and grade crossings more often. I think that's because space is at a premium and it's perhaps easier to make an underpass in an urban area than an overpass. In the end, I want to make a route that others and myself will enjoy (with lots of low poly eye candy [haha an impossible task perhaps?

] ) so I will probably make what looks best with some degree of reality...
I'd also like to add the next stage of my question (which I forgot to add). How about rail going over rail? Is it cheaper to go under or over? In that case, I think it would be cheaper to go under but I find the rail overpasses look better somehow. For example, I have a mainline and a massive car plant on it's left. I didn't want the autoracks blocking mainline traffic when they entered (the main line is only double tracked at that point) and even if the entry curve was gentle, the owners of the plant decided after seeing the underpass and overpass look

that they'd opt for an overpass as it's in the suburbs and land isn't too expensive and wont cheese off the mainline track users, but you get my drift.
The problem is, I first layed the tracks so the topography doesn't exactly dictate the choice of tracks, but yeah...anyhow, thanks everyone for your input.

Haha, I might have to do some relaying at this rate (which I find I keep doing the more and more I detail a route...).
:wave:
Gisa ^^