How "safe" is 5.2 to use?

[David Meier]

Hello list,

I am relatively new to the world of FreeBSD. But first, congrats to the
new release! I am somewhat insecure on how trustfully I can use the new
release for my intended use (and I hope my questions haven't been posted a
zillion times before). Therefore I hope the FreeBSD nuts can advise me
whether to go for 4.9 or 5.2.

The setup:
hardware: DELL PowerEdge 1750 (Dual XEON, 2GB RAM, RAID 1).
web server: Apache 2.0, MySQL 4.0, PHP 4.3.4, Perl 5.8
mail server: Postfix, Cyrus IMAPd, Cyrus SASL, Amavis-new, SpamAssassin,
ClamAV

The servers will be used for virtual hosting as a small ISP evironment and
housed about 30min from where I work (in case I have to reset them...).

I don't know how and if the instability risks may affect such a setup of
services on the hardware described. Unfortunately, the advisories are kept
in pretty general language, however, I know it is hard to predict how it
will be running on a particular system. I just don't know FreeBSD well
enough to have a 'feel' about it (although I don't rely too much on
'feelings' in the world of computers). Is upgrading to 5.2 comparable to,
say, I upgrade from RedHat 9 to RedHat's newest release?

What I like about the 5.x releases is the possibility of taking file
system snapshots, for example to back up the mailboxes.

Thanks for all input. Dave.