concerned about receiving a possibly defective unit

I purchased this cup turner to customize some cups. I used it once with a very thin layer of epoxy before recieving an email from the seller stating that I might have recieved one from a defective batch. I emailed them asking if I should return it for a replacement. The emailed me back stating that since I purchased it with a coupon code, they would message me on Facebook instead of through Amazon. I do like that it has a switch that allows me to change the direction that it spins but I am now worried that it might stop working or that the arm will fall off and wreck my cup. This did come with lots of extras like glitter, silicone measuring cups, tape, silicone brushes, foam cup inserts, etc. I plan on using this for a longer period of time and will update this review to see how it performed or with the sellers response if something should go wrong with it.