Well, I checked out the OEM cylinder and the aftermarket cylinder that the saw came with. Both are OEM 353 style semi-close port. The aftermarket cylinder has pathetically tiny ports, and on top of that when you check timing with the port cover off at bottom dead center, only half the port gets uncovered by the piston! The OEM cylinder is a bit better, but the piston still blocks part of the port at bottom dead center.
The flow would be compromised in either case, so I can see why porting these cylinders is a popular job.
OEM and aftermarket cylinder compared, the port size and piston position at bottom dead center. The aftermarket cylinder is really bad, I can't see how this will flow much at all. Going with a base gasket delete makes matters even worse as it drops the cylinder and blocks even more of the port.
So the aftermarket cylinder is pretty much useless as is and is going to be used as a porting subject. The transfer ports will be widened considerably and raised slightly in part to make up for the base gasket delete. The intake is fairly generous and won't be touched, but the exhaust port will need some work as it's a bit on the small side.