Magic Gem:
The Magic Gem is the strongest ball I currently have in my bag. We see plenty of overall motion with this ball as it reads the kids very strong and continues very well. This ball is designed for those heavier oil conditions or when they're absolutely walled and you need the ball to get ramped up early to fight those tighter conditions.
I see myself using this ball more on sport conditions versus house as I typically need a cleaner reaction on house to blend out the pattern more which provides additional miss room. For those who liked the X3 from Roto Grip you will enjoy the Magic Gem.
TNT Infused:
The TNT Infused is an excellent benchmark symmetrical ball to throw when the fronts begin to hook early yet provides tons of mid lane read. The Infused will be more usable for most players against the original TNT as it provides much more back end reaction and doesn't see the fronts as early as the original.
I have found success using the TNT as a step down off my stronger balls like the Magic Gem, Eternity PI and Xponent. I am a big fan of this ball as it provides plenty of usability when I need to  open my angles up on those medium to higher volume patterns. The Infused will be good on varying patterns from house to sport.