I can tell you from experience that if you're testing any of these, run them in Sandboxie or a VM on your hard drive (Sun VirtualBox caused the fewest problems for me on 64-bit Win7). Their uninstall routines don't clear everything out of the registry or networking setups; neither does Revo Uninstaller Pro.
Adding and deleting several VPN apps, each of which creates virtual network ports leaves enough mostly non-functional ports behind to confuse Windows 7 beyond its ability to cope. I didn't end up with a catastrophic mess, but did spend a week cleaning out a lot of relatively small but annoying messes, many of which kept Windows from recognizing many of its own files, or running the routines designed to fix them.
If you use corporate VPNs, aren't worried about encrypting your traffic in a coffee shop, but still want to watch the Sweet 16 without raising a red flag on the NetOps consoles, free or low-cost proxies might be the way to go. They also allow for actual anonymous surfing, rather than the browser-based version, which just means your laptop doesn't know what you've been looking at online, even if the whole Internet does.
If you or a significant number of your end users also bring-their-own tablets or phones and use them to get inside the firewall in a significant way (not just viewing email through a web interface), the problem may be even more complex because of the variety of devices and, often, incompatibility of the operating systems with corporate VPN or other security software.
So what's the story? How worried are you about your own wireless networking and what do you do about it? How does it differ from what you want your end users to do?