That's not what the spec sheet says. big.LITTLE is not just about clock speeds, it's about mixing low-powered and high-powered cores, using them when needed. The 650 does have a big.LITTLE set-up, the 630 hasn't.

My claim is that for most intents and purposes the XA2 isn't (much) faster than the JP1, despite the much newer tech.

From Wikipedia: Cortex A53 scores 2.24 DMIPS/MHz; Krait 300 scores 3.39 DMIPS/MHz. Converted to their maximum frequency on these devices: A53: 4928 DMIPS. Krait 300: 4746 DMIPS. Based on this, the A53 at 2.2GHz is barely 4% faster than a Krait 300 at 1.4GHz.

Sure there are other factors, and yeah the 630 has four times the cores, but I'll kinda doubt you'll notice that when doing some browsing.

Given my experience with a A53-powered device, I'm not too compelled to buy another one.