Looking at Bitcoin IRA

Started the process to transfer a 401k from a nursing job I just left over to Bitcoin IRA. They let you customize how much of your assets go into Ethereum, Litecoin, Bitcoin, etc and what percentage should go to each cryptocurrency. Now this part is huge--by putting it into a ROTH IRA...you do not have to pay any taxes at all when you withdraw any of it later on as long as it is after age 59-1/2! Roth IRAs, whether it is stocks, whatever, allow your capital gains to grow exponentially, theoretically, without worrying about tax consequences when you withdraw at the age limit mentioned above. Of course, you do not have to withdraw any of it at age 59-1/2...that is just the earliest you can withdraw without any penalty. I also have other IRA and 403/401 vehicles for stocks and mutual funds as well as I do not believe in having all eggs in one basket--which protects from some sort of worse case scenario like a Black Swan event that would render cryptocurrency. Useless in the future. But if Ethereum, Bitcoin etc go "to the moon"... it sure would be nice later on not to have to pay taxes when cashing in some of it, eh?