There is a lot of signal to noise on stuff like this. It works for some people and doesn't work for others. Unfortunately it's not a one size fit all kind of thing. What you should do is pay for one month and monitor it over the course of the month. If you notice a significant improvement then keep using it. If it doesn't help then stop using it and write a feedback letter regarding it's performance. I have not tested it myself, as I have good internet and latency, but a tank I play with couldn't survive standard dungeons without it. Her latency has literally been cut in half. In fact it's such a visible difference that I can finally start doing dps as WHM in most dungeon instances now.