NS&I Underrated by this website

IGK

I'm not a higher-rate taxpayer, but I do have a reasonable proportion of my savings in these certificates, and, as my example above shows, they have performed very well indeed. Not as well as some risky punts might have done (and by that I don't mean savings in Icesave or anything), but I want to sleep at night and not take risky punts.
OK, the point can be made that RPI isn't a 'real' measure of inflation, or that it's all a fiddle, but even taking the RPI as it is, these certificates have performed extremely well.
Now, RPI inflation may or may not fall, and if it does, the return on these certificates will fall accordingly, but then if that does happen, deposit interest rates will be lower too.