At least for foreign residents of Japan, I think ABTC is faster and easier than the e-gates. As a foreign resident you still have to fill out the paper re-entry card and get manually processed by an officer, and the e-gate just adds an extra machine to that process, so it's a net negative in terms of efficiency. The e-gate is really only worthwhile if you travel enough to use up all of your passport pages.

ABTC also lets you skip the line in many other countries...