I've heard that filing a tax return online is pretty simple so just wondered how many on here do it themselves.
Oh yes very simple until you are not sure about a question and you contact the helpline and they are no use at all .
That was my experience a few years back , I used to do my own accounts and tax return  for 8 years but as the years went on it more complicated more so the online form . 
At least with a good Chartered  accountant you are certain everything is done right and its peace of mind at least it is for me . Mike