Preferable Minimum Framerate?

I know this is probably a matter of preference, so I was wondering what logic I can use to determine what I would want to set my minimum framerate to in my game. Also I would like to hear your opinions for what you used and the thinking you used to reach this decision.

From the manual:

The default minimum framerate is 30 FPS, meaning the maximum dt is 1 / 30 (= 33ms). If the framerate drops below 30 FPS, dt will still not exceed 1/30. This has the effect of the game going in to slow motion as it drops below the minimum framerate, rather than objects stepping further every frame to keep up the same real-world speed. This helps avoid skipped collisions due to stepping a very large distance every frame.

I'd rather have my game slow down than skip frames and risk skipped collisions or other issues, so I set mine to 55 because framerate usually fluctuates a bit.

Well yeah I read that, but I was wondering if the fastest object in my game moves 16px per frame in my game, if I should set that higher than 30 or lower than 30. The manual didn't really detail any calculations I can make to fine tune it.

I've set it to 15 inside my game, C2's collusion checks work fine even on lower framerates for the most part.

The only problem with skips is when the framerate isn't stable and drops extremely fast, for example when creating 1000 sprites at once.

I also recommend to use dt in all of your movement based events, that seems to help with this issue as well.

I default to 60 fps minimum for my game. Just my own personal taste and I don't have any lag issue.

I put mine at 28 because the only objects that move super-fast that could screw up, use for loops to check collisions between points A and B, thus making this problem irrelevant.