Apple list 2009 iMacs as compatible with High Sierra so I don’t think it’s a stretch to expect it to work, no.

https://www.apple.com/macos/how-to-upgrade/#hardware-require...

I've got Windows 10 installed and working on a 2006 MacBook 1,1. It just got an update to 1709 Fall Creators Update, and still gets the usual weekly security patches. Something is awry when Microsoft is able to provide support & security patches for Apple devices longer than Apple itself.

It’s supported so it’s not a bit of a stretch.

SSD’s were generally available but extremely expensive from Apple so I went for the extra space on the desktop. For some reason Apple makes it difficult to upgrade their hard drives. I bought an SSD MacBook Pro at the same time. It was much faster with only a Core i5 vs the iMac’s i7. Barely used now because I bought another laptop in 2013.

Now, I wanted to wait for the next Intel refresh. No point in getting less than 32GB in a laptop in 2018 when I got 16gb in 2013. Because of the slow change in Intel revs, I’m probably better off cracking open my 2010 iMac and putting in an SSD.

Hey, thanks for taking me back and explaining how it was “back then”. I miss the late 90’s back then when I spent $800 on several hundred megabytes of 10,000 rpm Cheetah SCSI drive, and had that thing screwed in within 5 minutes.

The bottom line is you will basically live with your Apple hardware as you bought it for 5-10 years. Better buy at the proper Intel revision and get the upgrades at purchase. That 1 port on your new MacBook Pro won’t go far