Yeah tried on safedice, the 0.5% house edge is great but the rolling speed is awful, perhaps due to my bet is low i guess
Bitsler removed that feature i guess, previously we can see that but i couldn't see it anymore, not sure if they removed :/
yeah, they removed the flash bet feature from bitsler, i don't remember reading about "why" but my guess is it was because they grew too big so fast and making that fast bets was not possible.
and remember that all the dice sites will slow down your bets if you are making very small bets, the limit is different and many don't mention it but it is usually below 1000 satoshi bets.
this means if you really want to test the rolling speed you have to test it with higher amount than that limit.
also remember that your internet speed (ping) will affect the speed too.