If no one plays in a casino who will ever write a review right? Maybe just do a test deposit of about 0.001 or near that just to try out all the features of the casino and play with that. If you can, you should probably also try out their withdrawal feature.
I believe usually people do start with new gambling site only with faucets or free giveaways given through this forum. In another cases, like you have mentioned some big whales will throw away some test amount for this community. I mean to say there are a lot of possibilities to have review for every new casino. So, there will be enough meaning on waiting for reviews.
Playing in new casino is good in terms of free games in the shape of bonuses and giveaways but we have to take care to not to invest too much money in these gambling sites as these are not the trusted sites and when they spend some time among us then we have to trust on them for big bets.