neither really. the switch back then, in 98/99 iirc, happened because we were dissatisfied with both suse's and redhat's package management systems - pure rpm without yum back then, suse had yast, but it was all pretty "closed" as to what package-repositories got access to yast.
Suse and RH both were companies who had commercial interests as opposed to Debian which is (was?) a non-commercial "volunteer organization". The former have always tried to "sell" what was actually just a compilation of free software; in the beginning Suse argued they would basically just charge for the printed manual and (afair) 1-year of free support.
Debian didn't try to sell anything.
Add to that that apt, Debian's package-(repository)-manager and -system was far superior to Suse/RH's we decided to give Debian a go.
With the possibility to easily add 3rd party repos and with the "stable" branch always being stable as a rock - old, but well tested software - and with "unstable" being bleeding edge and actually stable enough for desktop use, it was the perfect fit for us.
Us being my best bud and me back when had the "honour" to set up a start-up company who out of a combination of stupidity and luck got a 2MBit/s connection for free in the middle of nowhere (at times where a local college had a 9,6KBit/s). We needed servers (motherboards in beer cases) and DNS, SMTP, POP3 and HTTP fast - whatever that was
So much for history. Sticked with apt-based distros where I got to choose. Like Ubuntu/Mint for ease-of use. Still have administered many rpm based servers over the years, including RH, CentOS and the likes.
So why I do prefer them now - I don't know. I'm a man of habits
Not really. I'm a tail/grep guy. But I have used munin for monitoring and monit for alerting for many customers' machines if you're looking for something like that.
Munin
Easy, proactive monitoring of processes, programs, files, directories, filesystems and hosts | Monit