Some questions about QOS and Performance

Hi,
Our company is a VPS provider , Currently we are looking for a QOS solution and intrusion detection system for our network. I have the following questions :
1.We have a fixed amount of internet bandwidth coming to our private rack in datacenter ( for example 1gps ) and we want to share it between all VPS’s with equal share. can RouterOS do it ? please note we do not want to limit each IP individually , we need a hardware which can do traffic shaping dynamically based on how much BW is being used.
2.Is the performance of RouterOS benchmarked ? how much throughput it can handle ? if we have for example 5000 VPS’s behind it , can it handle the QOS and traffic shaping ?
3.Is it better to use RouterBoard for our purpose ? or install RouterOS on a powerfull x86 system ?
Regards

http://wiki.mikrotik.com/wiki/Manual:PCQ

I think, it’s better to use some x86. something like powerouters? =)

I am douing this config at a couple of places with a second hand x86 PC with 200-300 Mbps load.