I-bonds Pros.
- interest is tax deferred so can be easily owned outside IRA
- easy to buy and sell. No commissions involved.
- Protection against inflation showing up in CPI
Cons.
- Fixed rates are way low (<0.5%) now. Used to be 2-3%
- You are now limited to buy only $5000 or so per year.
- Govt. can understate CPI and then you won't get the inflation protection you desired.
TIPS bondsA great article at morningstar (subscription may be required.)
http://news.morningstar.com/articlenet/article.aspx?id=358415&pgid=fundarticlePros.
- No limit on how much can buy
- Protection against inflation showing up in CPI
Cons
- Transaction costs. (Can not buy from govt. at face value. Must pay broker cost if selling before maturity.)
- Potential annual tax headache if bought outside tax advantaged accounts.
- Govt. can understate CPI and then you won't get the inflation protection you desired.
- Short duration TIPs are selling at negative rates now. So returns are not expected to be high. (You may beat an equivalent bond if CPI inflation >1.5% or so, but your absolute total return will not be high.)
- If you buy something in the secondary market with high embedded accrual, you may actually lose money in case of deflation. (Please reference the article for details.)
- How these bonds will behave if interest rates rise may not be straightforward.
TIPs mutual funds/ETFs - Same thing applies as above except that you may be able to buy without transaction costs at NAV and at least you will see a distribution for your taxable income.