Since I haven't seen any pictures... I'm assuming "etch" is being confused with
abrasive. I mean it's DIAMOND particles = they will polish anything if rubbed hard and long enough. Etching is purely chemical and would leave a "chemical-burn," and blackish pitting in the surface of the substrate from ion-exchange.
It's long been established in OC'er forums and by @home enthusiasts; IC7 IS superior to AS5 etc. And IC7 doesn't at all require the burn-in time as AS5:
[Website]
During the CPU's initial use, the compound thins out to enhance the filling of the microscopic valleys and ensure the best physical contact between the heatsink and the CPU core. Then the compound thickens slightly over the next 50 to 200 hours of use to its final consistency designed for long-term stability.
50-200hrs?! Ridiculous IMO, that's way too ambiguous of a time span to even consider as "reliable" for a "proper" burn-in and testing. What website has 50-200hrs to let a machine run Prime95 just to assure users of proper temps? I'll stick with ICD7 now that I've reconsidered the issue... too bad it's $$$!
ICD7: ... Apparently the only competitor close/equal/bettering in some cases is
Cool Labs Liquid Pro. There's an Ultra-100% metallic-solution that's supposed to be even better than the Liq-Pro. <--- From the few reviews I've read; it's about as good as MX-3 or slightly better, but not than AS5. I didn't see anything about it being conductive (METAL solution...)?