DO YOU GUYS USE THE "ATM' BALL DIFF. I'VE TRY IT AND IT IS SO COOL AND SMART DESIGN (EASY TO ADJUST). ON THE OTHER HAND, I GUESS 'ATM' WILL NEED BETTER QC. IN THE FUTURE. IN POSITIVE WAY, IF YOU FIND SOME PRODUCT DOES NOT SATISFY, IT IS BETTER REFLECT THE
PROBLEM TO RC SHOP OR PRODUCER LET THEM TO FIX. AND FINALLY, ALL THE CUSTOMERS CAN ENJOIN RC.
