PDF exchange viewer alternative for mac. | Mac

Hi everyone, I switched from windows a while ago and I love it. However some programs is what I really miss about windows. Particularly PDF exchange viewer. I study quite a bit (i’m a resident) and I am constantly looking at multiple pdfs at once.

I was wondering if You guys have any experience with PDF viewers that can handle multiple pdf simultaneously, Search within them simultaneously, annotate with many options and colors. I’m willing to pay for this. Of course the standard is PDF exchange viewer. I’ve looked up others but wanted some actual feedback from someone who has used them.

Heres a link to a couple of them which I have heard good things about:

Thanks for your time.