Hi,
The air con in the Premium is definitely a plus if the weather is very hot
However, air con aside, we much prefer the Standard 2 bed.
They've crammed more facilities into the Premium (e.g., a 2nd shower & a full size fridge). However, this leaves it feeling very cramped, e.g., there is hardly any walking space around the double bed, and the shower cubicles are tiny, with no ventalation. Unless you leave your ceiling to floor curtains wide open in the lounge, they also feel very dark and pokey.
Unlike the Standard, which has 2 bedrooms + a sofa bed in the living room (my kids love to lie on this in the evening and play cards/watch tele), the Premium doesn't have a proper sofa/chairs in the lounge. You simply have the wooden dining table chairs and a narrow bench seat along a wall (much like you'd have in a pub).
The Standards may look a little tired in comparison to the new ones, but they have much more character, and more of a log cabin feel
We were offered a Premium upgrade during our Christmas break, and turned it down much to their surprise.
Others may disagree though!