Thanks chaps for the info. 205 litres will be fine for us. We run commercially.
The other reason was simply that at £23-25 per 4 litres its too much of a factor per run.
The 3rd reason is simply me being tight!!
the drum of 205 litres will be brilliant. My local dealer didn't seem to be aware of it so maybe a call to barrus tomorrow?
thanks for info