Even when it dips in 120fps its still another than PS5
The frame-rate mode is intriguing for a number of reasons. Both PS5 and Series S target 1440p60, while Series X aims for 1440p at 120fps. Barring a drop from 4K in the quality mode, the presentation is essentially identical otherwise, the exception being screen-space ambient occlusion quality is dropped, with a lower precision effect in place on the frame-rate mode. Of course, exclusive 120fps gaming on Series X is a real coup for the machine but there is a catch - the delivery isn't as solid as I'd hoped, especially in the first Mass Effect's opener. Stretches of play will hit a sustained 120fps, but crucial locations like the Citadel sit between 80 to 120fps, with even the opening Eden Prime mission struggling to rise above 100fps for crucial battles. Again, dynamic resolution scaling is in play in this mode too, but it sadly can't always help it lock 120fps.
All told, whether it's down to the backwards compatibility nature of the title or some other factor, Series X has many advantages over PS5 - a tighter grip on 4K60 in its quality mode and a 120Hz mode that, while inconsistent, can be salvaged with VRR.