Coffee Appreciation

Is there a big difference between letting the grounds steep at room temperature vs. in the fridge?

Is there a big difference between letting the grounds steep for 12 hours compared to, say, 20 hours?

You'll get a stronger brew the longer you leave it.
It is already stronger than traditional french press coffee.
I prefer mine brewed 8-10hrs, in the fridge.
There may be a little difference between in and out of fridge, in theory you're getting different concentrations of the oils seeping out.