Misleading Pricing

So a few weeks ago we were looking at holidays. We were comparing prices between Travel Republic and Sunshine holidays. Sunshine holidays had a much cheaper cost overall for 5 people (Around £300 cheaper), same hotel, same flight. So we think great we'll book through them. So as you do we inputted all the required information and at the final stage it brings up a message about how the flight price has nearly doubled in the short time it took us to put in the details along with some rubbish about how this sometimes happens.
So I decided to give them the benefit of the doubt and opened a new web browser and punched in the same details over again and yet again it brings up the cheap price to begin and then doubles it at the last stage! So we booked through travel republic as they do not advertise unrealistic pricing.
I did however decide ok maybe there system hasnt updated so now after a few weeks I decided to put in the details again today and see what it came up with. Guess what? They are STILL advertising the low price at the first stage and increasing it at the final stage. If the price has realistically gone up then ALL sunshines systems should update the instant it finds out the price has "increased" The initial search should pull up the updated price.

Clearly this company tries to pull a fast one and draw you in with a low initial price only to increase it substantially at the end of the booking process. My advice, stick with travel republic as they don't try to pull a fast one at the end of the booking process and have a much wider choice of hotels.