I haven't found any rates for callable CD but I will give advice on cash accounts in general. I will echo Nothernbeaver's advice and research the institutions you are wanting to work with. Make sure they do not have a history of fraud and are FDIC insured. Now whether or not you should invest in callable CD depends on you, on your age, your timeframe, and what you plan to do with the money.
Are you are saving for a trip or to purchase a new toy? Then it might make sense with FDIC insurance the money is safe and you receive a better rate than a savings account or noncallable CD. Though the maturity date and early withdrawal penalties could be an issue. Since I read they can have maturity dates of 10-20 years but being unable to find any offered I don't know.
If you are looking at it as a way to make money in general. So not saving for something specific and having a 10+ year time frame. I would say no it makes no sense.
My personal philosophy is to invest the bulk of my money in a broad based U.S. index fund something like the S&P500 or a U.S. total stock market index. Smaller amounts go to alt investments and specific stock picks with the expectation of earning returns in excess of the total U.S. stock market average which is around 7-8% per year. I use small amount of money over many varied investments to help offset the additional risk of investments failing or underperforming verses an index fund.
I am going to guess you are interested in CDs because they are safer than stock. They certainly are less volatile and if you have a short timeframe that is important but they really aren't any safer than stocks. The average return for total U.S. stock is conservatively 7-8% per year. That 7-8% figure is not what to expect your account to grow by each year but it is indictive of the long term trend of the U.S. stock market. The generally given advice is if you can hold your stock investment for 10 years you can weather most financial crisis. As for the money just going poof if the company goes under, this is eliminated by using an index fund and not picking individual stocks. A company like Vanguard with 9 trillion dollars of assets under management is not going to go under and God help us if it does.
Basically if you have the timeframe to hold stocks until they rebound they are clearly the superior choice. And remember niche things are niche for a reason. For most people they don't make sense.
