Why don't you want to use testing, again?
Well, it doesn't have security updates (well, testing security team is supposed to exist, but it seems somewhat dormant as of late). I may give it a try, though - I'm not running a server so it shouldn't be too bad.
Backporting isn't always automatic, packages change with time. Right
now, it is probably not so bad, a simple "apt-get build-dep foo; apt-get
-b source foo" might work because etch has not been released a long time
ago. But as lenny grows near, more and more packages will need manual
backporting.