Another subtle FX difference: Phaser 2 has a parameter for "LFO Phase Difference," which Phaser 1 lacks. Found that in the QY70 List Book, which seems to be as thorough as it is detailed.
Looks like absence of other caveats to other FX params in the docs indicates each numbered preset is the same algorithm under the hood. Was ambiguous to me before, but this makes sense now.
J