Sippdeal is cheapest for shares, Alliance Trust Savings is cheapest for funds. The last time I looked at this, I think I concluded that Hargreaves Lansdown would cost me tens of thousands of pounds more than Alliance Trust, over an extended period of time. Someone more energetic than I am right now may be able to post a link to my previous post containing the example calculation.

The payment of commision is going to be banned soon, then it will become clearer to many people how much they are really being charged.