I think the biggest thing to look out for when using boolean operations in other modelling programs is that it often creates n-gons - i.e. polygons in your mesh that have more than 4 sides. In general its a good idea to avoid having n-gons in a model - they often don't display properly when you import them into another application - I've had troubles with models I made in Lightwave that have n-gons which I have imported into Vue and bryce and poser not displaying properly. Quite a while ago, some much better modellers than I am warned me against using boolean operations ni general.

If you made your model in max out of nothing but tri's (three sided polygons) then your exported max file size should be similar to the bryce obp size, assuming they're both untextured. But then, if you made everything in max out of tri's you may find that the exported mesh is much bigger than if when you made it the way you do at the moment.  What you gain one way, you may lose in another.

What I do is I make all my models out of quads (4 sided polygons) and tri's if possible and then import that into bryce. Yeah, the saved bryce obp is bigger than the exported obj file, but it works and I can live with the increase in file size and the biggie - the model displays correctly.

Hopefully thats of some help.

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