Hey, cpaolo
Universal Audio interfaces are amazing. It might be overkill to use an Apollo Interface live, but if you want premium sound quality, you can’t go wrong with these.
I’ve been using Komplete Audio (From Native Instruments), but it’s not that great. That is a budget option. I feel it lacks brightness and overall presence live, but it’s not terrible, either.
As far as mono goes, 95% of my gigs use a Mono PA.
My studio interface is a UAD Apollo Twin (2017 mark1), but for gigs I’m using a Steinberg UR22C, which is a good budget interface ($150). It’s for sure better than a $40 m-audio!
Chasing a RME Babyface Pro FS, but it’s currently unavailable. 
I still use two UR22 MKII with my redundant system. They are solid and I never had a problem so far.
The MOTU M2/M4s may be a good choise too.
In the past I used interfaces from Cremware, RME Multiface, Steinberg MR 816, SPL Crimson.
I did extensive testing of the Behringer 202HD interface a while back and believe it or not, the DAC side measures quite clean as long as you can keep it 3dB-4dB below full scale output at all times. The A/D/A chip isn’t top shelf, but its solid. The fly in the ointment is the analog section runs at 5VDC which is “minimalist”. I suspect all the cheaper IOs have this issue.
But there’s no meaningful digital loss turning down the output in the interface’s mixer so the analog section doesn’t get hammered and then make the gain up at the board. Do this and a/b with something high end and it sounds quite respectable imo, even in reference cans. Plus no great loss if it takes a beer bath or walks!
I know since I have two 404HD as backup. Despite the low price, the sound is surprising good. Too bad the cracks&pops during power on and at the start of the DAW/Host audio engine. So I limited their use at home only.