Left my vehicle at Onnie for 10 days without issue.  At this EP there is a berm that you can park behind to be out of sight of the roadway if you wish.  The parking lot is right along side the roadway ... the berm is just beyond and on the opposite side of the road.

I've always seen several vehicles parked at the Leano lot, but its a bit of a hike off the main roadway compared to Onnie and Johnson EP's.

dd