Using a Grandmother as a controller for Logic

[Twinkiebus]

Hi all! First time poster.
I’m VERY close to purchasing a grandmother. I only own a handful of keyboards and the GM would be my first moog (as well as my first semi-modular).
I am currently using Logic with my Korg R3 (8 voice polyphony) as my controller.

Here’s where I need advice...

I am pretty much sold on the GM in all respects but I’m considering trading in my R3 for credit towards the cost of the GM.
I need to preface this next part by saying, I’m very green when it comes to midi, in general (the majority of my music experience is with drums and guitar).
NOW. If I lose the R3, I will be relying on the GM as my midi controller for Logic. Is this a bad idea?
I know that the GM has midi and USB functionality but I’ve read a lot of people are having some issues with the GM in Logic.
My other concern is (forgive me, I’m a bit of a noob), if the GM is a monophonic synth, does this also mean that it will also be monophonic as a controller in Logic, or will I be able to use it as a controller in the same way I use my R3 as a controller?
If not, I’m going to guess that I should hold on to my R3 and just eat the extra $200-$300 I would have gotten as credit towards my purchase.
Thanks so much for all of your help, in advance!