That's interesting bro, a lot of people I've heard from have said they don't grind well on metal and that's my experience as well, just realized they are coated, and tbh mine aren't super broken in for grinds, so maybe that's the issue. Idk, on the stop and chat recently Schmitt said they are closer construction to thunders after I think Crob said he heard the same thing you're saying...closer to Indy, I never measured but anyways, they really don't feel like either or to me...they are kinda their own thing, really light...turn decently...grind well on most things, but they are too light for me at this point, I need more foot pressure from the board for flip tricks, a heavier truck gives you that, that in conjunction with cupsole shoes, I don't feel the damn board much on basic flip tricks lol, so I find myself missing flick a lot. They allow the board to flip and spin freely on its axis with very little drag, but the foot response is weird, I don't want to get used to it. The grind issue I had with them on metal isn't really my issue tbh. In fact, I think I'd like the non magnesium ones more probably. Also I really like that I personally didn't need to change out the bushings for bones which is what I run in thunders, that interlock thing they are doing is nice. I definitely recommend them if you are looking for a light truck and don't like the other "advertised as light" trucks out there. It's scary how light these make your board. Windy days you'll know your board is light lol.