I had the pleasure of sitting through one of Quest's (formerly Vizioncore) webinars today, and had a chance to review all of the best practices that they have with vRanger 4.5.
One thing that always stands out is the settings in vSphere 4.x for the Service Console. You should set 1500Mhz CPU reservation and 800Mb memory reservation. This will give you optimal performance on your hosts for the best/quickest backups. Then you also need to make sure you adjust your settings inside vRanger to match what your equipment can handle (how many jobs one host can handle, how much throughput your data store can take), so that you can do what vRanger does best and push data as fast and hard as you can to your backup store. That is, unless you are a 24 hour shop; then you might want to throttle it, depending on how cheap your equipment is :-)
This obviously only applies to ESX. ESXi doesn't allow vRanger to get in and work the same way, so they have some other fancy tricks for ESXi using the vStorage API. You can read about it here:
Cool stuff. And it all works awesome. I ran across a comparison chart the other day in Quest's blogs that show that vRanger outperforms competitors by 3-4x on LAN-based backups, and by 1.75x on LAN-free backups. Check it out:
And in the interest of full disclosure, I don't work for Quest. I'm actually an agnostic when it comes to this (as I am with most software; I like what works, don't like what doesn't), and have implemented and managed multiple different VM backup software - including Acronis and Symantec. They all have their good sides and their bads (some more than others) but if I have a client that prefers a particular product due to loyalty, existing service contract, or the classic "I am already familiar with their console," I'm happy to help them go with whatever they want. Ultimately, it's their job, not mine, that's on the line if the product doesn't work as advertised by the manufacturer - and I always list the caveats so that they are aware going in.
Here's some books that should help out:
Mastering VMware vSphere 4 (Computer/Tech)
VMware vSphere 4 Administration Instant Reference
VMware vSphere 4 Implementation