Anyone invested in' PIBS'?

[universalcurrency]

I was trawling through the FT and came across a listing for  permanent interest bearing shares (pibs).  The yield on some of these 'shares' looks quite spectacular eg 'co-operative group instalment repayment notes' @ 17%

Therefore I was wondering what the catch is with PIBS in general eg can the share price be very volatile, or possibly worse high spreads when it comes to trade?

[vand]

The problem with any of these instruments is that if the sound too good to be true then they most likely are too good to be true. In this case it just looks like a junk bond by another name. They may be paying 17% but that probably reflects the risk of default.