Considering 2nd Bike, 125 2 stroke?

So I currently own a 2016 YZ250F and have always been on a 4 stroke since I started MX (only been riding about 3 years now, minus a deployment in between). I found a great deal on a new YZ125 and was looking at possibly picking up a 2nd bike. I love the idea of having variety in my garage and a back up bike in the case something gosh forbid happened to my 250F. Im a bit of a mechanic and understand the maintenance aspect of both, like the simplicity of a 2 stroke engine as I've never done much besides a top end on a 4 stroke 75 hours or just before. My concerns are 2 fold, a) do I really need a 2nd bike, lol, maybe stick that money in a disaster 4 stroke incident slush fund b) will it hurt my progression riding. I understand 2 strokes tend to make you a better rider, but I have friends who both advise against and for one saying it will and others saying it will put me back. Little background C rider, old guy, weekend warrior, 155lbs. Just looking for everyone's thoughts.