I used to live near the original Olley's in Herne Hill - they are wonderful - it is worth the trip. The branch of Olley's in SE1 is awful - their fish and chips are NOTHING like the spectacular original.
I got chips for an extortionate £1.95 from that new 'proper fish and chips' place in Borough Market. They were only just cooked and there weren't many. Why are good chippys so rare? It can't be that difficult.