manic mechanic sprocket vs CNC sprocket

[southern Cruiser]

I have ordered a 40 T from manic mechanic but I also see these CNC sprockets on gasbike.com for a lot cheaper. Just wanting to know the pros and cons between the two if anyone knows. And if they can be mixed together as far as mount and sprockets. also I'm wondering what kind of speed I will get out of this 40 T compared to my 44 T. Right now I can get up to 29 MPH.
I weigh around 160

 

[butre]

assuming you've got 26 inch wheels and your motor turns 6600 rpm, you should pick up about 2 mph by switching to a 40 tooth

if you were using a rag joint before and are now switching to a sprocket adapter, you'll have improved drivetrain efficiency and won't see a major impact on acceleration

 

[southern Cruiser]

Yes, 26" and 6600 rpm. anyone know about differences between quality of sprockets?