If you're referring to the K&N drop-in filter, yes, the POP is better. It replaces the restrictive intake box with a large-element filter, allowing for better intake flow and more HP.
If you're referring to a universal round K&N filter with MAF adapter, like the one on ebay, I really couldn't tell you for sure which is better. The auctioneer
here is claiming a 6 HP increase. I tend to take everything I read on ebay with a grain of salt, though.
The JWT POP Charger and $tillen's copy of it both come with a MAF adapter with a radiused inlet like this:

The radiused inlet helps to prevent turbulent flow through the MAF which can cause problems. So, in that sense, the POP is better.
In conclusion, the K&N
may produce power(because it has a larger filter element), but since it lacks the design features of the POP, I wouldn't want it on my car.