The 350 was slower, more spacious, better views
....
Do LM still offer a trolley service anywhere?
TPE do. £2 for a cup of tea is still a rip-off though.
ATW give me a trolley service on my manchester-bound commute on something (170ish?) too, it's great. I rarely partake, but nice to know it's there.
The fast LM services from Stafford to London aren't that much slower - an extra 40 minutes, but if you arrive at the station between :42 and :55 and the quickest way to get to London is the xx:55 LM service, rather than waiting for the next :42 VT service. The fact it's more comfortable (and cheaper) makes it a very beneficial service.
From Crewe it's less clear-cut, as the Stoke dogleg adds another 30 minute penalty, so finance comes into it (LM is £60-100 cheaper each way). While Virgin put on empty 11 car long distance trains like the 0930 CRE-EUS I'm currently on (8 people in my current coach), LM have overcrowding issues.