I have used cheaper strokers but not the fleshlight brand ones. From what I have seen, the fleshlight has an opening similar in size to the Bad Dragon Mare, and I can vouch for my dick when I say a long vagina-slit shaped hole doesn't grip in the proper way, whereas a smaller, circular hole is much better.
Right now my cock is about an inch long and as thick around as my pinky, decent growth for just applying topical stuff and then starting T a month and a half ago. You want a hole about that size or smaller most likely.
The POV anal DVD and stroker kit has an amazing stroker that works very well for me, and I will be writing the review on that soon.
When picking a toy, remember that if you have a pre- or non-op cock you probably want to stick with a stroker that doesn't come in one of those fancy cans because your dick won't be big enough to push the air out and if you can't squeeze the sides in you won't get suction. Cheap jelly ones have done me wonders.