At that time of day I would say yes as the station is usually very busy.
My advice though is when asked to present your tickets and are then asked for payment to present a card rather than cash. The last three times I have been in the KX lounge the member of staff hasn't known how to use the machine or it's been broken. Twice I have just been waved through and the time I was asked for cash I said I don't carry and that I would have to go to the ATM, I was then just waved through.
It's nothing special tbh just hot drinks, water, coke, crisps, biscuits and if you are luck there will be fruit.
Alcohol is available to purchase. I wonder if when it changes to VTEC if they will install a bar like Euston.