DOn't know about anyone else, but I'm betting 95% of the adapters come from the same factory in China. Personally, I'd love to see a quality 510-eGo adapter, made of SS, instead of the crap we get. Tired of stripped threads. The adapters I have on hand all are unsealed, I wonder what would happen if the adapter was sealed? Food for thought, maybe I"ll solder one up and see if there's a difference.
As for using mesh, there's a vid floating around on youtube somewhere that shows someone doing this. I would think that rebuilding a T3 head with 500 mesh would eliminate all wicking issues with high VG juices, but I haven't tried it yet with a T3. Everything I vape is 50/50.