Recently the Intel UHD 620 and Nvidia MX250 driver got updated by Dell so I installed them. With both now using Sharpen AI 4.1.0 the times to update the screen are about half of what they were when I posted the above info. Also, now choosing Auto in preferences is faster than choosing the 620 or MX250. I don't know if this change is because of a difference in this version of Sharpen AI (4.0.2 vs. 4.1.0), the drivers, or both.
Update: In 4.0.2 I couldn't find how to choose features for my monitor either so had to do Auto. In 4.1.0 Auto seems to be faster than choosing for some reason. Also, the update sets my minimum resolution to 2560x1440 so I may need to restart the computer since it doesn't work while developing. I'll continue to report.
New version of SharpenAI has now come out. You can see the details below. If you download the new tar, you can unzip it, copy the files to your downloads , and then type sh./update_faq.sh to automatically update the software on i.gigapixel4. Instructions below the download link. d2c66b5586