This thread discusses both Miyota movements fairly well. I would expect them to be comparably accurate and durable. Also search the forum for other threads on either or both movements.
https://www.watchuseek.com/f71/miyota-9039-new-thinner-than-9015-a-4670601.html

 

Is there any difference between 9015 and 9039 apart from the date part? Which one is better from a user point of view and why?

They are identical except for the date ring and the crown's date setting position on the 9015.

 

No date complication, all else is the same. From a user perspective, the only difference is the 9015 has an extra crown position for date quickset, and obviously the presence of a date display.

 

I believe - in addition to what's been mentioned - that the stack height is different.

 

Nope, same height. Pretty often the case, so they're completely interchangeable.
https://miyotamovement.com/product/category/Premium+Automatic/

 

On a somewhat related note, if you have a "hidden date" watch with a Seiko NH35 it's perfectly interchangeable with a no-date Seiko NH38:

https://www.watchuseek.com/f74/converting-true-no-date-unimatic-u2-project-4493515.html

If you have a "no-date" dial watch with a Miyota 9015 that you want to convert to true no-date, I believe the better swap is the Miyota 90s5 because it has the same stem/stack height. If anyone has done that conversion please chime in.

 

I believe Tisell uses the 9015 and 90S5 for their date and no date versions, respectively, of their Submariner homages, so it definitely seems like the 90S5 is the better choice as a drop in no date replacement for the 9015.