Its a serious question and want to know your opinions, i have never done anything on this webiste before. I just created a account and this this roll you can do every hour, but that seems meaningless.
Is it worth to invest some btc there for annual interest rate or anything?
Very subjective.
If you invested in FUN tokens way before 2022, you're likely facing a loss because the other coins went to shit.
Currently prices are more or less the same so losses or profits are somewhat negligible. Because you gain the Premium membership, you are rewarded with free spins which slowly increase the longer you keep them along with some cashback or interest here and there.
But from the free spins, they're not all Sats so you get some lottery tickets and reward points thrown in.
If you simply join to claim the free sats, then it's definitely not worth your time. You need to "gamble" more so the reward base increases. Also, the site offers 4.01% APR if you store at least 30,000 Sats which the interests are credited daily.