Rev cgi upgrade question

[jbv]

Hi list,

I'm about to re-design a web site that I built around Rev cgi
in 2004/2005. Back then I used Rev cgi 2.5 Linux.
Because of several new features, the site might get significantly
more trafic than before, especially in tasks requiring lots of
requests to mySQL.

I was wondering if it was worth upgrading to 2.9 or if I could
stick to 2.5...
Besides, because of the possibly increased trafic, I'm planing to
switch to php for some scripts (the more used ones) because of
the multithread advantage of php. Although I was wondering
whether the most recent versions of Rev offered increased speed
that could be an alternative to the use of php...

Thanks in advance,
JB