Advice on what device is best for photo editing.

Either a MBP or iMac will work, however what is critical is that you buy the correct tool for the job. When you both the 21.5" 2019 with only 8GB of RAM and glacially slow 5400 RPM HDD you did not buy the correct tool. You bought something that was designed as an e-mail and web surfing appliance. An analogy is you bought a MiniCooper when you should have bought a 2 ton Ford Truck.

Whichever you decide to go with let us know before you pull the trigger and then we can help you select the correct configuration. For example if you get a 24" iMac get 16GB of RAM, the 4 port model and the largest SSD you can afford. If you get a 27" iMac get an i9, select the antiglare display, get the largest SSD you can afford and buy with only 8GB of RAM, you can still upgrade the RAM yourself (the 24" models do not have upgradeable RAM) by using OWC (www.macsales.com) or crucial.com RAM. I'd suggest getting 32GB add it to the base 8GB and then you have 40 GB of RAM which is enough for most heavy lifting.

When it comes to selecting a laptop or a desktop, the ONLY thing that matters is do you need portability or not? If you need portability then clearly you need a laptop. If you don't get a desktop.

Your welcome. What I would recommend is the following in a 27" based on your needs:

• NNano-texture glass
• 3.6GHz 10-core 10th-generation Intel Core i9 processor, Turbo Boost up to 5.0GHz
• 8GB 2666MHz DDR4 memory
• Radeon Pro 5500 XT with 8GB of GDDR6 memory
• 1TB SSD storage
• Gigabit Ethernet
• Magic Mouse 2
• Magic Keyboard - US English

If you want more storage you can upgrade to 8TB of SSD storage (expensive) . If you have a window to your back that allows glare to come in, keep the Nano Texture glass, however if you do not you may not need the Nano Texture Glass. Buy 32 GB (2 x 16 GB RAM) from either Macsales.com or Crucial.com. Doing so you will see a huge upgrade in performance over your current computer.