Ah right I forgot I already had putty and freecap setup as we've been running our own guild ssh server for over a year.
You can configure the two applications manually, or you use the registry file generated by the site. If you're worried you can open the .reg file in a plain text editor (like notepad) and look at the contents. It's all just settings for putty and freecap.
As I said we've run our own guild SSH server installed on some cheap linux web hosting for around a year and a half. Recently the host started having network problems at about the same time as wowtunnels decided to go free based on donations.
A lot of us switched over and have been using it for ~6 months. I would say 60% of our raid is using wowtunnels and the rest are either using our guild ssh server or something else.
The first popular pay ssh tunnel service for wow that came out was
LOWERPING.COM - lower ping for gamers basically halving your ping is such a night an day difference there are many sites offering this type of service now. It's not very complicated there's just a matter of finding a good/cheap US host and doing it.