Denial of Service: Commercial Defense products

[Ogle <myinfosec () gmail com>]

Hi,
I have an ISP customer who want to protect their network and their
subscriber's network.
In "Internet Denial of Service: Attack and Defense Mecahnisms" book, I
noticed 7 commercial products.
1. Mazu Enforcer by Mazu Networks
2. Peakflow by Arbor Networks
3. WS Series Apliances by Webscreen Technologies
4. Captus IPS by Captus Networks
5. MANAnet Shield by CS3
6. Cisco Traffic Anomaly Detector XT and Cisco Guard XT
7. StealthWatch by Lancope

Since I'm new with this type of products, is there any reference out
there to help me choose the right solution to my customer ?
Is there any problem if I use IPS (ie: TippingPoint, McAfee) for this solution ?

Thanks.