Personnaly I'm fond of the Fog from X-Vapes (topgreen), it's convection, it's fast to heat, fast to extract, works perfectly for micro-dose if you add a screen on the top of the load, very stealth, replacable battery and easy to use.
Maybe I'm not objective since I review/test most of their products (for free) although I wasn't rating positively some of their vapes (Vital and some others) but I'm thinking this company make a good job trying to offer some affordable quality vapes without to copy any existing design/tek.