No... no need to buy the ported ones unless you don't want to do the porting yourself... I buy the un ported ones then do all the port work myself. I'm sure the ported ones he sells are good but I'm really picky about port timing, duration, and the physical width of the ports. If you look at the intake port on his 40mm bolt spacing cylinders you'll see that they are round and smaller than the ports on the 32mm bolt spacing cylinders... this is great for those who want to do their own thing with the porting and good for those who just want to bolt on and go, the intake port starts out at 19mm and tapers down to about 16mm at the cylinder with a long straight shot into the engine which makes for a lot of torque in stock trim but still capable of a lot of rpm up top, that taper accelerates the air going in so it can pull in more air than there's room for at higher rpm's which makes for higher transfer pressures and even more that can get stuffed into the cylinder when in its powerband, which equals more power to keep things simple. With a custom matched intake and an 18mm carb this would make excellent power as well as really nice torque down low. The transfers have the flat tops and they are nice and wide as well as being aimed nicely so all that needs to be done here is the typical casting ridge cleanup.
The exhaust ports are also about 25mm wide on these so they're pretty much ready to go right out of the box, but you could open the exhaust up to the 29mm limit, then all that's needed is to raise the roof if more rpm is desired. Otherwise the 40mm bolt spacing cylinders are pretty much bolt on and go performance, with just enough room for the finishing touches to get the port timing where one wants it to be.
The 32mm ones are very similar except that the intake port is typical where it's short but wide... also really good for top end power but with enough room for end user improvement if desired.
The ported cylinder in your link is nice but you would need to find out from him where it's timed for so you can know how thick the base gasket needs to be for best performance, but it looks like it's set up for at least an 18mm carb and a good pipe which should provide excellent performance for someone who prefers not to port their own cylinders... some of the bikes his customers have are Really fast so I'm pretty sure his pre ported cylinders should be good too.
These are the ones I buy... http://www.ebay.com/itm/MOTORIZED-BI...-/271894008452
And these... http://www.ebay.com/itm/MOTORIZED-BI...-/271952264441
There's also quite a price difference if you can do the porting yourself....