Hi,
I am still new to the whole NBE thing,  so definitely not an expert,  but here is what I experienced:
Kangzhu - I first started with them for a couple of weeks
Pro - it is quite cheap
Pro - It has nice rubber around the edges, so doesn't hurt your chest
Con- I really struggled to keep the pressure which meant that I had to pump every now and then.  So I couldn't do anything else
Con - After my second use,  one of the airlock bits fell off,  so I always had to do a bit a maintenance before I start.
Noogleberry - I switched to NB after a couple of weeks on Kangzhu
Pro - More professional system - definitely better quality
Pro - Suction lasts.  I pump and then I can go and do other things and it keeps the suction.
Pro - Bigger sizes (XL and XXL)
Pro - great customer service
Con - Much more expensive
Con - it doesn't have rubber rings,  so it took me a while to get used to the cups.
Bad effects = As far as I know,  you will have issues with ANY system if you overpump.  I suggest you read some of the threads on the forum about NB and Kangzhu as it will give you a better idea of overpumping etc.
All in all,  I think both systems can work.  If you have the money, I would suggest NB,  but it is just because I am lazy and like the convenience of pumping and then going on with my life.
Hope this helps