The Aspire ET-S and Vivi Nova Pryex BDC tanks in my opinion are the best out there right now.
No leaks, no gurgles, great TH, and lots of vapor. Very well engineered and the 'fit and finish' is top-notch.
Plus they're less expensive than the Kanger units. Now in the 'looks' department they are quite 'retro' looking but I am not concerned about how they look, my concern is how they function. That's the important thing, hands down.