I have one of each.
There are both okay mics.
But my 435 is modded.
Better components.
It is the better sounding of the two mics.
My friend has a stock 435 APEX.
She likes it and uses it as a vocal mic.
I have heard some of her recordings and her vocals sound decent, using the stock 435.
I personally like the APEX better for instruments than for vox.
The CAD M177 isn't bad, on some voices, either.
But I do have some higher quality CAD mics, which sound better for vox, that aren't much more expensive than the CAD M177.
Both models are okay, for budget mics.