The end result will be the same. They both are very well made, and will vape well, when properly set up. They are quite difference in appearance and layout. Bliss has a shielded tank. The ZAU doesn't. The Bliss has 5 openings in the top deck, allowing for several configurations. The ZAU is a single mesh wick unit, with an insulated wick hole, which some people remove, some don't. The Bliss has a threaded top cap. The ZAU uses o rings to attach the top cap. The Bliss has 2 very small vent holes, 180 degrees apart. The ZAU has one, which can be adjusted to line up with the wick/coil.
I'd weigh the differences, and see which would work for you.