I tried them in the early 2000's on a Windows 98 machine. Chopley recently sent me a copy of all the latest ones so that after I refurbish "the beast" (the machine I bought when MGS got so bloated it no longer worked on the old PC), I can try them on something more capable, and with a screen big enough to run the larger emulations such as Doctor Who, which didn't work properly because the buttons were off the bottom at the largest possible resolution on the old PC.
I haven't been up the motorways for years, having found online casinos, and later the MGS versions of AWP games.
The main factor though was the free for all that followed a relaxation of the rules around 1996, where the stake and jackpots grew much faster, and much of the true skill feature games were replaced by pseudo skill variants. It was then all about the emptiers, and it was hard to figure some of them out. Most of the ones I got came too late to make much, as I didn't feel like paying the four figure sums that were being asked for early knowledge. I joined a couple of subscription sites, but it seems they were set up by people more interested in nicking our findings than sharing information about possible emptiers.
Pie Factory wasn't a true emptier, but it was fun and almost risk free provided you didn't try it on a machine that had just been "done" by someone else. When they got chipped, they missed the one at Frankley services near Birmingham, and I did this one every time I passed through
I also liked seeing the countryside and northern towns and cities, and I wandered right around the motorway network, including going abroad to Scotland at times.
My best times were in the early 1990's, where it was more about skill with the features and less about knowing emptiers. I did know that ACE machines were riddled with bugs and emptiers, and had fun with "Pay Rise" one Easter, making over ÂŁ1000 in a week despite "everybody" also doing them.
Many of the best players relied on persuading others to give them lifts, but I had a car and could change my plans if I heard that another group of "players" had gone before me on a particular route. Machines close to the big cities were almost always "dead", as they were being fought over, so I looked for machines away from the big cities, and the Lakes had a couple of "Pay Rise" machines that the others couldn't reach easily, and so I had them to myself for the week.
If I hadn't been working full time back then, I would have probably become a full time travelling "player", and would have had more time to devote to working out the emptiers. Mostly, it was down to figuring out who the skilled players were, and watching discreetly and trying to figure out what they were doing. I noticed that most emptiers involved "sparking" the machines to force them to reset in the middle of paying out a win, not exactly discrete, even though they tried to hide what they were doing by playing as a group to shield the machine from prying eyes. Switching off and on at the wall socket had the same effect, but "security" was on to it.
Despite going for the more discrete, if less profitable, methods, I was still kicked out of quite a few places for being "too lucky"
I decided that motorway services were a good bet because there was no arcade owner looking over your shoulder, looking for any sign of being too good at the game and chucking me out. Motorway staff had no personal interest in how much money the machines made, so they rarely, if ever, intervened. I have seen some pretty blatant* "emptying" at a services, yet staff still can't be arsed to go and investigate as it is more work for them.
* blatant - as in cordless drills and other tools.
I never bothered getting a refil key, as I might as well have worn a T shirt with "I am going to empty your machines" printed on it, both attracting unwanted attention from "security" and scaring away other players who are needed to keep the machines topped up.
My trademark was the carrier bag, which contained reading material for when I decided to grab a coffee and watch the machines from the cafe if I felt they might be worth a "force" in an hour or two, but needed to take a little more or show more promising precursors to a "streak" event.