I commuted from Bolton to Manchester on the train for just over a year. I used to buy a monthly ticket, and I found that I could upgrade it to First Class for not much money. I think it might have been about an extra 10 of 15 quid / month?
priority seating, hot or cold drink, and a snack twice a day in a comfortable, cool, quiet coach with power sockets too.
There were the odd very busy times when first class woud be declassified and everyone and anyone would be let in but that was fine as you could apply for a refund if you really wanted to.
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the only challange was knowing if first class would be at the back or front of the very long train - I learned to spot the difference from a big distance and go tot he right end of the platform.