I own several Bulletshare bonds, each with a different maturity, ranging from a year out to three years. Now, I've had two or three mature. Have yet to discover any drawbacks. Easy to buy; easy to hold thru maturity. Very easy to ladder. I wouldn't put a ton in them. I also have bank CDs and Vanguard muni bond funds for fixed income diversification.
Happily I haven't tested mine in a terrible recession (like 2008) or in a period of raging inflation, but they should be pretty safe in tough times.
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