HuntWyld - The side buckles are standard, not autolock. We have not had any issues with slippage, these are the same Duraflex sidelocks we use on all of our packs. That being said, we do offer autolock buckles as an accessory for our packs for specific usages, so those are available if you prefer.
PRM - We use Duraflex buckles throughout are harness and packs, I believe they are compatible. If there are any issues, we also have quick attach buckles that can be used to convert to one style.
BR Snow - While you can attach the range finder case over the buckle, I would suggest trying the extension strap that is included with the range finder case. It will replace the quick detach buckle on the side of the harness and move that buckle location out from under the range finder case velcro. This is how I designed the attachment, it keeps the range finder case tight to the harness and will not allow it migrate down the webbing, the velcro lays flat over the webbing and is more secure, and it does not create a hump where the buckle is as this keeps the range finder from riding level against your chest.
In the photo you can see the short webbing extension with quick detach loop on one side, buckle on the right. I used a coyote colored extender so it is easier to see in this photo. This extender will replace the 1" quick detach buckle attached to the harness. When then placing the range finder case over the strap, I suggest nesting it down as low as possible, this creates the most secure connection as is shown in this photo.
Also, you will see that the shock cord on the range finder case is routed back up through the webbing loop after length is set. The first batch of range finder cases we sent out had knots tied at the end, which will work fine once set as well to keep the shock cord from any slippage. However I prefer to have the routing back up through the loop as it is cleaner and provides adequate friction to prevent slippage.
Best,
Kurt
