I have never bought more than two or three FX motors or any other motor at any one time. I have not had a real need for more to test or look for THE hot one. If you are in it to win that much, why are you playing the DIII fun game. Go back to Div I or II.
I might get a good one, an average one, or a dog. I make do. There are things to be done with it besides giving up . . . SCMs can't, I guess.
If I get a real dog like a couple S7s I got, I may have to buy one more or switch but thats about it. Of course, I am old and slow so who cares? Why do I even bother to come down to BP?

Sheer waste of my time and others.
As far as going with that turd 16D overweight piece of junk, I would rather quit slot racing. I have not raced one in at least 15 years or more. I think there is one broken one in a drawer here somewhere to remind me how bad they suck everytime I happen to see it . . .
Now a C-can motor like the Speed Fx is a bit different story, as it can be made to handle somewhat better. But it's still a bit overweight.
Maybe a three-motor limit can be put on the selected FK motor chosen and they have to be bought from the Div III supplier with a serial number on them.
The fun part ot DIV III is the scratch building of chassis and the Can-aAm cars themselves. Plus the people who come to have fun.
If it is all about winning, why are there any racers beyond the first eight in the A main? Let those eight run, crash, and burn to find the one big winner. Or maybe the fast qualifier should be the only big winner. Why fight it out beyond that, seven of them will lose!!
Second place in any race is still the first loser. So why really bother with the race? So if you don't make the A main go home, watch the gam or mow the lawn. It would be more productive.
I come down because of the fun and the people who show up. Not because I have to win (a joke) but because of the building, the fu and helping others by promoting scratchbuilding. The race is secondary to me. It is just some icing I can lick off the big cake of fun.
Just another point of view of why winning seems so important beyond anything else to some. That the cost will drive them on or to lose their interest when it becomes too much to deal with. Why did 35 racers even show up? Only one can win in reality. So get a life.