I didn't until recently Jan. I can see it causing problems - when I had my IPA I didn't have it reassessed if my expenditure went up a bit, I used some of my surplus. If I hadn't had that I would have had to contact the OR regularly.
i think with the new rules and the £20 allowance that they (the Or ) will be overrun with us / individuals continuly asking for reviews of our Income and expenditure.