Yes, this is cheaper than the 2 for 1 because the 2 for 1 prices have to be paid at the gate which costs £55. So, even at 2 for 1, you are paying £7.50 less this way. Although if you are going with a mate(s), then all of you have to have a student ID with a valid expiration date on it. Or you could use Student Beans to get a code for your mates and send that code to them for them to buy them. Yes, the Student Beans method is slightly more expensive (by a couple of pounds) but still. Just putting it out there.
Better than the 2 for 1 offer which can be used on the day ?