Generally, yes, but if you’re in a mixed environment than Firefox makes some sense because at least for me, I want cross-browser syncing on all of the devices I use most. I have a PC for gaming and the occasional need to use a PC at work, so I keep Firefox on iOS for this type of thing, but that mostly just acts as a place to push things to from Safari.

Even if they do use the same browser engine, the feature sets may be worth it. Orion, for example, I really wanted to like and work well since you can use a lot of the desktop add ons in both the Firefox and Chrome add-on store, but it was just too buggy to daily drive.