Yeeah, I don't really get what Grog was thinking here. Have gone through two bottles of this ink now, and I still haven't found a point where it outperforms Buff Proof Ink.
The penetration is at times a bit TOO much. As a result, your newly applied and seemingly opaque layer of ink will at many times simply fade right in front of your eyes as a result of penetrating into the substrate. While I can see how this probably makes it stick around for a while on a porous surface, it also often leads to a "meh" result.
When doing a side-by-side buff test of Street Killer and Buff Proof Ink, Street Killer was covered up by two layers of paint LESS than BPI. So if choosing between the two; BPI is the way to go in my opinion.
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