When I have multiple scripts in /etc/cron.hourly/ using noanacron do they all start at same time or sequentially? I would rather they all went at same time in case one takes close to an hour to complete.
Sequentially. This is accomplished by a line in /etc/cron.d like this:
01 * * * * root run-parts /etc/cron.hourly
and `run-parts` is a bash script which goes through in a loop (with logic to avoid certain filenames and to implement random delay, but not much else).
I think good practice is to only drop short-running scripts in that directory; longer jobs should get their own /etc/cron.d entries.