I am aware of the problems with import/export, and I too wish it were easier to use. I wouldn't call it hopelessly broken. More like slow as molasses.
I work around the performance and timeout issues by breaking the XML files into smaller chunks, and running imports from the command line, where you aren't subject to the short HTTP request timeout setting (I think that is normally 1 or 5 minutes?). It takes
30 minutes for me to import ~10,000 content items. The total file size for the XML i import is ~10MB.
I think Sebastien has also suggested other workarounds, I can't remember exactly what it was, but there is a way to implement some interface and get control over the import process to get around the performance issue. It was a post on this message board
if you want to try to search for it.
Dealing with the import/export issues is worth it to me, because it gives the ability to use a console script to recreate an entire site and populate the db with content immediately after checking out the source from my private Hg repo. This is useful for
setting up development environment on a new laptop or after a reformat, and also when you're like, "Daaaaamn duuuude! I just fucked everything up! Oh well, let me just restart from scratch... *runs ...\src\orchard.web\rehydrate.bat* ". I periodically
update the xml data with exports from production, so our development environments on our laptops always generally look like production. The process for doing that is easy, just export from production, and update that xml file in version control.
I can't say enough how helpful it has been to have a development process like this, where you feel free to totally mess up anything in your local environment because starting over from a fresh, working copy of everything is easy and takes no effort.