Yackie is right. The mentioned guy is named Markus Hauschild and is managing his one-man-adventure together with his brother and his Thai wife.
I have contacted him several times since I bought a GT-SIM in 2006 for allmost 40 EUR and after I recommended this SIM to my boss who is a frequent traveller.
Mr. Hauschild is a very pleasant phone partner with one big fault: 99% of his promisses, sentences ot whatever are naked lies.
The last big one was with the replacement of the old dead GT-SIM (Callkay) with a new one. The first time the excuse was: Oh, of course, but in your details I just see that you've ordered your SIM over gt-sim.de. But we first replace the orders over gt-sim.com, please be patient for 14 days. This one was repeated 2-3 times from september 2007, now we have Feb 2008
I doubt that somebody actually has received a new GT-SIM from him.
Another story was with the dual-sim-phone. He meant the first charge of 50.000 pieces was literally swallowed by their distribution channels so one has to wait 2-3 months untill again deliverable. But... has somebody this phone? Any test, any opinions? Negative... a little bit strange considering the 50.000 phones that are in use...
The third myth was in connection with a new product of GT-SIM where the minute rates for all networks in Germany should be less than 8 ct/min.
And so on...
Now he is selling another GT-SIM with another roaming partners (at least for Bulgaria there are all 3 networks listed, the old one had 2 roaming networks there) with setup fees of again 40 EUR and cheap minute rates. But how reliable is this card? How long will it survive?
As gt-sim has vitually NO support - apart from the big stories of Mr. Hauschild - and no information system if somethings goes wrong, this time I will not play the early adopter and will abstain from this offer.