100%ed the game, my opinions: the slot machine is quite awful of a grind but everything else was fun
it was for both, I very luckily got a jackpot and Reeler before hitting 999 quartz spent total for the achievement, problem with the slot machine in my opinion is that it cumulatively takes too much time for the 999 quartz achievement because of the time to do a spin, and takes quite a while to get enough quartz (even if you get multiple small/medium/big wins) to the point where it feels it really interrupts the established gameplay loop and really puts the final nail in the coffin of the "okay I can ignore most of the ores now" problem in the end of the game, hope this helps!! aside from the slot machine this game is really great though, definitely scratches the itch for 2010's flash game vibes, which is a very rare but VERY welcome feeling in games nowadays
I agree the slots can feel grindy, especially with Reeler unlock tied to a jackpot. I'm planning to adjust things in a future update so Reeler unlocks after a set number of spins (~100 spins), and the Jackpot Junkie achievement triggers from a jackpot instead. Thanks so much for playing and sharing your thoughts!