Interesting... How would you quickly compare Arch vs #! vs Debian?
However, arch breaks things often, very often. You make updates crossing fingers you will be able to reboot. Debian, crunchbang, overall, is very stable.
It depends what you want. If you are not a linux guru and need to work on your system, then go for something easy and stable like debian, otherwise do go for arch.
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Yes, I talked all the time about Debian and I missed #!. Let me say, crunchbang for me it's just an easy way to get a debian testing. I prefer it like this as last time I used Debian it had some rough edges I have no time anymore to smooth over. I want things to work out of the box and a good community, check #!, they actually have a nice welcoming community.
That's kinda what I expected, an out of the box OpenBox setup built on top of Debian. It does say they use packages from their repository so there must be some differences than if you did it yourself.
As great as Arch's documentation is (best in all linuces I've tried), I still prefer to have some nice defaults so I can get stuff done whilst learning the knobs.
I've only had one update issue, otherwise, it's pretty been reliable.