BaseCamp Slow

On my Mac and with my Garmin RV 770 it is very easy to install a map that is (only) on my device also on my computer:

0.) Make sure that BaseCamp is not running on your Mac.

1.) Connect the device to the computer and wait until it has mounted on your desktop.

2.) Start Garmin Express and click onto the icon of the connected device.

3.) Click onto Map Options.

4.) Click onto Install To Computer and let the magic happen.

5.) Disconnect the device from your computer.

6.) Start BaseCamp and check under Maps in the menu bar that the now installed map is selected.

7.) Create your trips or whatever in BaseCamp.

8.) Connect the device to the computer when you want to transfer any trips or other data.

Even with the device connected to the computer you can still use the locally installed map instead of the map on the device. For that it is a good idea to always first start BaseCamp before connecting the device.

I would assume (but, of course, don't know for sure) that this is working in the same way with any other Garmin device.

I have Basecamp 4.8.4 on a 27 inch late 2015 retina iMac with 4GHZ I7 on macOS 10.14.6 and it is SLOW  but Basecamp 4.7.0 is not so something happened during the transition to 64 bit.  This was reported months ago and is still not fixed.  Garmin has released some cool new GPS's lately,  the 66i and 64x, but I will not buy until they spend some time fixing Basecamp so it will be a pleasure to work with again.  

I also have an i7 Mac with macOS 10.14.6. BaseCamp 4.8.4 is not particularly slow here - certainly not slower than the previous (32-bit) versions on previous versions of macOS. However, I use it with locally installed maps, and that might make a difference.

I doubt that Garmin will ever bring out a truly "newer" version of BaseCamp. They seem to keep it kind of alive - but that's all they do.

my garmin express doesn't give the option to install locally. 

if I connect the garmin edge it all works fine, so i'll just use this to create routes, save them to the computer and then connect the watch solely to transfer the route.

that is unless garmin come back with a solution.

I have the same issue. Basecamp 4.8.4 is reacting irritatingly slower than the 4.7.0 version (on a 2017 27inch iMac). The basecamp version 4.8.4 reacts noticeably slower when I drag and drop a course. I have reinstalled the 4.7.0 version again (from Time Machine).

I use locally installed maps.

I agree 4.8.4 is way slower on my Retina 27 inch iMac than 4.7.0.  I also have locally installed maps so that is NOT the issue.  Unfortunately Garmin seems to have little interest in improving their software.  

Arghhhh. When you say slow, do you mean like 20 hours slow??? I've plugged my new Fenix 6 pro in my old iMac (but it's the same on a new macbook pro) and it's been reading the cards for... I don't really know may be 10 hours? And it still not fully uploaded. One map has been loaded (TopoActive Europe South West) but it's just so slow to use that it makes it unusable.

I've been checking a little bit around and I'm wondering if it's not this new USB Media Transfer Protocol the culprit. I'll try on a Windows to check.

did you find asn answer to this? I have the same problem.

no - this a VERY accurate description. I have a Fenix 5x and 6 pro... and I have exactly the same issues. It works like a charm when the 5 is plugged in and takes AT LEAST 30 seconds to refresh on the 6. 
Both OSM and Garmin maps have this. It's gotten so bad I'm drawing in basecamp with the 5 plugged in (which feels like a set back)