KVM over IP

Our company uses two 4 port KVM switches to do hardware/software maintenance and we are looking to replace them as they are about 5 years old now.
One of the requirements is that we can access connected devices over lan using rdp or similar.

Avocent has a solution that would work but is pretty expensive. I’ve paged trough the websites of a bunch of companies that offer similar solutions (belkin, opengear, Raritan, Adder etc) and they all offer similar solutions but I lack the experience to make a solid decision and was hoping someone could point me in the right direction.
A few things we are looking for:

- KVM over IP, trough RDP, VNC or similar.
- Must work well with any device and allow easy switching of devices.
- Must have USB support.
- VGA monitor support but must work well with vga>dvi converters.
- Should be a minimum of 4 ports with a maximum of 8.
- And this may sounds silly but I want it to be fairly easy to use. Both our system administrators as well as our Servicedesk will be using the device.
I hope someone can give me a few tips or pointers on things I should look for or things/products/brands I should avoid (and preferably why).
Many thanks in advance for any replies.

What about using something like LogMeIn?

or teamviewer or one of the flavours of VNC?

Thank you for your replies,

The great thing about KVM is that you can see the connected machine regardless of its state (unless its turned off).

In our companies situation the machines connected to the KVM will change a lot. The KVM will replace the current one on our workbench where we install and configure most our non-standard hardware. Being able to connect to the pc regardless of what state is in will save us quite a bit of time.

Now we have to walk to the box every once in a while just to check if everything is going as it should. With KVM over IP we could continue our other work while keeping an eye on the installation/configuration process.

We are extremely satisfied with our Smart 108IP from Minicom. They are just as good as the Avocent and Raritan but cheaper. Check them out here: Smart 108IP