anyone who ever tried different beta blocker especially propranolol and bisoprolol. does each beta blocker ability to maintain lower HR work differently?

i've known beta blocker since 10 years ago the first BB i got was propranolol. and that was the most i used but i feel it doesn't really help much. ever tried atenolol and metroprolol but im not sure the effect since either it's only for short and i didnt really pay attention/noticed. so i cant say, but if i'm not mistaken what i can remember it's similiar to propranolol.

anyway, lately the doctor changed from propranolol to bisoprolol. i've used propranolol for years. been only a week on bisoprolol. on really low dose. but noticed a different though i don't know if it's due to something else or my condition change by itself (it happens sometimes) lately i check my heart and it's calmer. but what i don't get is even after bisoprolol supposed to wear off (more than 12 hours) my heart still calmer. besides i'm on a really low dose. espicially compared to propranolol which i usually take. so i wonder if it's really due to the bisoprolol or not. but for days the difference was visible. so i'm not sure.

however if it's really caused by bisoprolol it kind of confused me and came up some questions: wasn't all beta blocker supposed to react the same? and could it cause some resistant effect?