Personally, I'm okay without AMP if 99.9 percentile latency on the overall mobile web ecosystem was within 2~3 secs. Unfortunately, it's more of 20~30 secs on non-AMP sites, which made me to take an ambivalent stance upon AMP. My ISP is obviously not doing a great job, but it's also a publisher side problem which is nearly un-fixable anytime soon.