Sigma 70-300 non APO vs. APO

I currently have the Sigma 70-300 non APO (should have done more research before buying). Never knowing a better zoom lens beyond 55 mm, Is it worth getting the APO version, or would I be better waiting until I can afford the 70-200 F4 L (probably not for a couple years). The other lenses in my arsenol include the kit lins and the nifty-fifty. I use the 70-300 quite a bit for the photography which I enjoy, but it is purely a hobby.

I'd probably keep it and upgrade later to another lens like a 70-200.

APO has slight advantage at 300mm. Both are soft at 300mm. But tad sharp at 70mm.