Given what you have seen this year, which is a better shooter overall…
A single flywheel shooter
a double flywheel - one on top and one bottom
or
a double wheel side by side (horizontal)
Just in terms of success in skills, most teams in the top 30 have single flywheels, while only one has a dual flywheel (1404B), and none have vertical dual flywheels.
Disclaimer: I haven’t seen all of the robots in the top 30, because not all have been revealed, or been shown in matches that I’ve seen.
because more and more gameplay nowadays has to do with how fast you can move and shoot on the field, I personally say that a single flywheel takes the lead in that aspect mainly due to it ease of feeding into
I know this isn’t one of the options, but slipflys are 10/10 best flywheels 
Single flywheel, hands down. Can easily shoot anywhere on field without angle changer
Slipflys? Are you talking about slip gear launchers like punchers and hammers? or something else?
He’s referencing a thread from earlier in the year about new launcher designs.
The “Slipfly” is a flywheel with a slip gear which could act as a kind of ratchet.
Obviously it would have major issues.
Oh ok… gotcha… Yeah that would have some major issues.
Personally I think the single flywheel is the way to go based on that it is goo from most any position with the right programming and velocity control.
I would say Single Flywheel because double flywheel is not accurate for full court and is so hard to tune (for full court)
From what I’ve seen from matches in the US, I would say Single Flywheel/Puncher combo (Puncher for match loads, flywheel for field balls)
The winning alliance at the UK Nationals had 2 teams with a dual flywheel (horizontal) and one team with a single flywheel/puncher combo
It’s all a matter of build quality to be honest. Judging by robots so far, single vertical flywheels seem to have the best success so far, but there’s no real reason a double flywheel shouldn’t do just as well.
Back spin.
You can set the entry point into a double flywheel to have the wheels touch the bottom of the ball, providing spin. It’d be harder to do, which again speaks to single flywheels being easiest to construct, but you could do it.
That’s not really true… My old double flywheel had 100% accuracy full court as long as the loaders did not go too fast. Double flywheels tend to be more accurate full field when done well.
You guys haven’t seen a proper vertical double flywheel…yet
@alex531 has a dual flywheel and 435 in skills, I don’t think he’s saying that it can’t be done.
I understand that (and nice job to @alex531 for that very impressive number) but he said that it’s very hard to tune, this is simply not true.
You can also put two wheels on each shaft, and put rubber bands around the bottom ones. That way the bottom wheels will put spin due to the fact that they will spin the ball faster since they are slightly larger.
I would say a single flywheel is the best launcher.
We have a very good double flywheel that easily does 2 bps full court and basically rapid fire at the speed of our intake. I just want to say that personally I feel that it is easier to get a good double flywheel working than a single flywheel because from my prior experience, it is very hard to get a single flywheel to get far distance. Also, double flywheels also have backspin. Ours has backspin and is quite accurate. My point here is I think that it all depends on the build quality and the amount of thought and effort put into building a launcher.