http://www.whaccessories.com/G-Pack.htm

worth it or would it blow the engine

For the GS?  :lol:

Speed on the GS is limited by the laws of physics, not no schmancy computer!

I assume you wouldn't even find anywhere to plug it in.

Or maybe you meant for your gixxer...  

It claims for work for the gs 500, for '04+ models.  "G-Pack works as follows": "Ignition 2nd 2900-10300 / 3rd 2300-10300."  Sounds like it acts as an ignition advancer?

The way most of those work are based on FI systems that have been retarded in 2nd and 3rd gear to pass emissions. Typically there was a throttle stumble around 3-4k rpms in those gears. They are just a resistor to trick the ICU to think it is a different gear or neutral. Same thing as an TRE (timing retard eliminator). In a FI system, there are different maps for varying rpms and gear position that alters fuel supply. Not sure what is different on the 04+ that would allow for this but the signal generator is different.

You mean "Hear" ... not Here ...
Cool.
Srinath.

What was pictured will do nothing but cost you money with a GS.  GS has carbs and zero computers.  
If it's for a GSXR or SV it sounds like a crock-O-bull.  It may improve performance, or not, but you'd be better off with a power commander or something that truely remaps the FI and ignition.

My buddy has one on a TLR. He said it makes more power but it's rough at cold idle.