I see you have had no response to your query - just bumping this up as I received a similar "special offer" pamphlet this morning and I have the same question.
I have done a bit of research on Google (GSL is a popular 3 letter acronym) and it appears they have won awards with this software from something called "Online Shares Magazine".
However, if you delve a little deeper, you find they are in fact GSL Associates, with a very poor web-site that looks as if it has been "under construction" since 2003. I don't find this very comforting for a technological company. These days, if your on-line presence is poor it tends to reflect badly on the company as a whole, rightly or wrongly.
I will be giving this company a miss unless anyone out there in the ether can persuade me otherwise with positive testimonials.
Dave