The E-channel is great, not sure why anyone would complain about it. Enrollment is easy, but there might be a line depending on when you arrive and go through immigration. But easily worth it. As previously noted, it's right after immigration, before you step through the sliding doors to the baggage carousels.

My barcode sticker is attached to the back of my passport. No more forms to fill out. Forget the order exactly, but step up to the first gate, scan the barcode, gate opens up, scan fingerprints at next gate, and you're through. All within 30 seconds...unless there are slow people who don't know what they're doing.

I enrolled through CX Marco Polo.