Ive looked in the forums as well in the past, the ARC products are just turtle slow!
For the Pro 106/197/651/652, whistler 1040,1065 I use PSREdit500 and it only takes I'm guessing 15 seconds to do while sending usually 95-99% of the maximum 1,852 main memory on the scanner and 20 scanlists(banks).
Download PSREdit500
If you haven't paid for the arc yet, use PSREdit500! (Made in the U.S.A) Has a free trial period as well, install it at least to compare.
In the IMPORT section of PSREdit500 it does have the ability to import Arc500 files so you wouldn't need to start from scratch.
I have arc96 and arcxt. but not arc500. While arc96 for the old pro 96/2096 doesn't take too long since there isnt as much those can handle, its seems slow.
The ARCxt on my 996P2 will take 55 minutes! Sending some 7,500 frequencies, talkgroups and 81 quickkeys (banks).
Only reason I use acrxt is that it can handle DMR, otherwise honestly I cant stand it!
Now on the 396XT/996XT with freescan and minus ~70 DMR stuff will only take at best say 3 minutes!
Using same computer a Dell XP15 windows 10.