I should be clear, I do own a gvg so I have had a chance to compare them.
I agree the gvg is perfectly suited to vaping spice. I have 7 screens in mine and if what I want to do is breakthrough, I can't imagine a better system. The glass allows you to see the milky white smoke when you are drawing on it and the heat is just right.
I just posted this device because I think it looks cool, and sometimes I am more in the mood to "sip" spice rather than blast off. With the gvg you are vaporizing as you draw, so it is important that the spice all vaporize quickly and evenly or you will waste some. With the flask, I take my time creating a "cloud" of vapor in the device using, as others have pointed out, convection. But unlike the gvg which requires a certain amount of skill and focus to use correctly, once I have filled my flask with vapor I have a minute or so to take the draw from it. So the entry feels a little more relaxed and non urgent. So that relaxed approach becomes part of my "set and setting". I'm not selling anything, just playing with ideas. Appreciate the feedback anyway.
Part of what got me going on this was surfing through vaporizer websites, I stumbled on a device called the "herborizer". French product, designed for MJ but their XL model offers variable temp control from 90 to 230 degrees so I think you could use it for spice at the low end of the temp control. I really like it's style but it's way too expensive to justify. So this little device is my homage to french style.