Honestly, like any other program, in the right hands it's wonderful. In the wrong hands it's a disaster.
Personally I prefer Illustrator. Mostly because I'm more familiar with it and it integrates better into the rest of the Adobe Suite.
I know years ago there were issues with Corel and transparency, I'd like to think those have been resolved though.
For me it's a no-brainer. Illustrator will run on my Mac. Corel won't.
But, even if I could run Corel, I doubt that I would. Illustrator works so well with all the other Adobe products. I use InDesign a lot in my freelancing, but my day job is in the packaging world, and Illustrator is the standard there. ArtiosCad integrates nicely with Illustrator. I can import structural design files, make 3D files, etc. No idea if Corel will do that, but I'm betting no.
I've been in prepress for over 25 years. Rarely met a Corel Draw file that I didn't want to cuss at. Being tenacious I usually get them to work but they do require some fancy footwork. There are some designers that can produce a viable file out of Corel Draw but they are few. I have used Illustrator over the years however the newer versions of the program are a bit complicated/convoluted and takes some getting used to. I have had less problems getting Illustrator files to produce good print files from designers than their Corel Draw counterparts. ~hope this helps.
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