The more I think about it, GC is generally a bad idea because the few times it works automatically, it is based around dynamic allocation. Static allocation is much faster. Now I like some of the convenience of GC, but I wish it could be turned off for some (most) classes.
Static allocation has a lot of side effects that lend to bad OO design and can make your app a memory hog. They also create other challenges for multi-threading (which, of course isn't an issue with BMax currently). If you have a lot of meshes, static allocation is going to consume a lot of your system resources, and those aren't let go even when they're not in use. With static allocation, you have to make a guess up front about what your memory consumption is going to be.
Sometimes you can get away with that. I'd guess more often than not, you probably shouldn't.