Acting on paid-for advice, I have not contributed to my pension for the last three years, instead piling what spare cash we have into a stocks and shares ISA. No relief at the entry - if you will forgive the term - but no tax on the exit. Swings and roundabouts. Oh, and a lot more freedom about what one can do with the resulting pot.
Personally, I would not trust an insurer with my pension fund in a million years now. Mine was built up with Equitable Life (and then raped), then moved to Norwich Union who killed it some more by being fecking useless fund managers. It is now parked as a SIPP, spread over some 14 different and best-performing funds and doing much better thank you, even though I have not contributed for three years (see above) and the Mrs Merkel re-election campaign has taken the shine off of it somewhat.
I am not an IFA and anyone intrigued by the foregoing needs to seek the advice of a responsible adult.