We tried BetFury and overall it's a good site, they process withdrawals quite instantly (or with a very small fee in Bitcoin if you choose the slow option which is not bad).
We have sent referrals and overall the site is quite rewarding, but here is a major problem which is some transparency in regards to the boxes.
I will explain it briefly.
If you want to buy one of the boxes you need to get to Rank 2, so you need to wager 0.1 BTC in total (over $1,130 as of today),
I spent around $20 in "fees" in order to get there playing the dice with the lowest odds and also using Crash playing the 1.01 odds on some large amounts which pose quite a huge risk to lose your entire balance, but thankfully it worked well. So the greyd-out button to buy the box became available:
I deposited an amount planning to buy 7 out of the 7 available boxes (i.e. invest in this site and believing it has a good potential) but this is what happens after buying 3 boxes when you try to buy the 4th box using the "Buy Box" button:
So basically you have to wager another $400 in order to be allowed to buy more boxes, and even if the 3 boxes expire and pay their dividends - you would still have to wager $400 (0.035 BTC) in order to buy these boxes again.
So by all means - this is not a great investment unless you believe you can spot these 1.01 Crash odds that won't fail you (i.e. won't hit 1x) - otherwise you have the house edge against you.
Still - don't get us wrong, it's a good website and it looks quite promising, the faucet (25 SAT every 20 minutes) as well as the other perks in the site make it quite attractive, and it's still worth the shot....
BUT
We felt the need to share the experience in regards to these boxes - they are unfortunately not a straightforward investment as it seems.