Having spent the last 48 hours mostly in Manchester I feel sufficiently able to appraise folks of my findings. These are not exciting but might save you some time and money. Firstly, the issue of paying for wi-fi in hotels. Let me list some reasonable places where wi-fi is free in no particular order, McDonalds, USA,Italy, Munich Airport and the Worsley Pub next to Worsley Park Marriott hotel. Now a game. Lets find a place where they charge 15£ for 24 hours wi-fi. Yes you guessed it the Worsley Park Marriott hotel and in fact all Marriott hotels in UK ( as far as I am aware). This is a disgrace. So my first recommendation is yes to stay at the Marriott hotel ( its rather nice and not overpriced) but instead of eating or drinking there, walk 200 yards to the pub next door and eat for less than the cost of the wi-fi.
My second recommendation is to avoid central Manchester. Signage would be better in Antarctica. The roads are crowded with folks all giving good impersonations of intractable ADHD, not able to wait at red lights, junctions or anywhere in fact.
My final recommendation is to avoid the Palace hotel. A miserable excuse for a hotel. everything was bad.
Good things? Norton Caines Services on the M6 Toll are the best I have found this year. But avoid petrol there. I can buy my diesel for 137.9p at my local south london Esso garage. Diesel at Norton Caines was 152.9p. Put it another way. Filling my tank there would have cost me an EXTRA £10.