What size for LOGSIZE and LOGFILES on OWS 7.22

I've read that LOGSIZE and LOGFILES and PHYSFILE should be made very huge. What would be an efficient size when you have about 50 users concurrent and a 4 GByte hard disk space. I've also read that OWS can only handle up to 32 concurrent users. Is this right? Many thanks already for answer, Pascal Schaefer