Hi, I was interested in using Merch by Amazon but when I read your informations, it's not so positive. I've seen a video on youtube about Merch by Amazon and he told that Amazon does the shipping and give you your royalties. But it appeared it's not...
Amazon merch has no support, no way to contact them, tshirts quality very low , and has bad printing smell... they have lots of emails so no way your email will be answered... I tried everything to get in touch with them it's a hopeless case ..
I used to sell at merch but after waiting for 1 month with no answer to my emails .. I prefer just to leave this service... aws support is the best support for Amazon they reply max within 6h while merch support is died!
It's a shame shame shame !