[TYPO3-english] Multible sites in TYPO3

[Jesper Goos]

Hi

I have a TYPO3 installation with currently 3 sites for one customer.
This customer now wants additional sites (3-5), and I am not sure if the new 
sites should be implemented in the same installation of TYPO3.
I have absolutely no problems with the 3 sites, but would like some feedback 
on when to choose a second installation, rather than adding sites to the 
same installation.

The sites have a lot of load, but the server handles everything fine, so for 
now no performance problems.

What is yout opinion? All in one, or is it better at some point to start on 
a new installation of TYPO3?

Thanx for any input ;-)
Regards Jesper