IMO it depends on how much you value a few hours of sleep. If it were me and I had to work the following day, I'd probably spend the extra money. On a redeye you won't be able to take full advantage of the food and drink unless you want to stay awake, but the difference in comfort for sleep, if that's what you want, is enormous.
I think Mint is both the best product and the best value of all transcon premium flights I've tried in the last few years (VX, B6, AA)...