To my ears, the Vali takes it with the Q701. It breathes life into the Q701.
The Magni, in contrast, makes music sound flatter, stiffer, more constrained, and generally less engaging and interesting.
In fact, there's not one pair of headphones I own where I don't feel this to be the case. I like the Vali that much better than the Magni.
The only area where the Magni betters the Vali, IMO, is in the noise floor. This is only a concern to me for my bedside setup, where I'm listening at lower volumes. Even so, I always switch back to the Vali despite the noise floor because it's more involving to me.
And one other area the Magni is better is in power delivery. I haven't had any issues with my phones being driven well by the Vali. OK, perhaps the the only phone I have that may be preferable with the Magni is the HE-500. Not sure, it's been a while. I recall the HE-500 to sound out of breath with the Vali.
Having said that, I can say that the easier-to-drive HE-400 sounds better with Vali though.
My recommendation for Q701 is for the Vali.
Thanks, guys. It seems like the concensus (at least in the Vali thread) is that the Vali is better with the Q701 than the Magni. I suppose I should probably also ask in the Magni thread. lol