I'll be honest, there are no journeys I've ever made where the quality of the rolling stock has determined whether or not I use the train. It's simply down to convenience of carrying luggage, fare prices and suitability of the timetable. Most of the long distance travel I do is at weekends, often bank holidays, which invalidates the GEML as it typically doesn't run on bank holidays. There are also parking charges to consider. Even if a 3-day trip would otherwise be break-even on price, three days' parking at my local station would bump the cost up considerably. One day's parking at Brentwood buys enough fuel to drive my car 80 miles. If there's two people travelling, forget it. As much as becoming a driver has been useful, it's really put a damper on how much I use the railways because the numbers just don't add up. It may be more effort and more dangerous, but if using rail doubles the cost of a journey (or more when travelling with 2+ people) and turns a 3 hour journey into 5, it isn't appropriate. I use the train for getting to London and to visit places during a single day that happen to be near a station.
If I had to visit somewhere very near to, say, Cuffley, I would still probably use the train whether a 313 or 717 would operate the service. If it wasn't near the station though, or there was a rail replacement bus, I'd probably drive.