All I can say is that I had one of those, but a half check, and I was always nervous about the clip snapping, so I now just use an ordinary half check without the clip.
I'm just struggling so much to get one to fit Henry, the buckle ones are either too small on one hole and too big on the next hole... I like the fact that you can adjust these to whatever size.
I had that exact collar (well, it was black!) for Ruby as her first collar, it never came undone of its own accord even if she pulled (although I have to say this was rare) or when she played roughly. However she had outgrown it after a few months and I think the clip was a lot 'looser' than it was new, but I never leave it on at home so it was put on/taken off several times a day whenever we went out which probably didn't help.
If you are clipping the lead directly on there is a risk they unclip when the dog pulls hard, and even if you are using a slip lead they can come undone anyway! Both of these things have happened with Otto!
However, if you have a dog that likes to prat around in brambles (Otto!) then they are safe-ish because if the dog gets caught by it's collar they usually unclip.
Sweep's old collar - very fetching red and white stripes before the brook and muckheap
- and his new magnetic collar both have those fastners and we have never had a problem. I never fasten a lead to it though as Sweep has a fetching padded half check collar and matching lead!!!
Hmmm Henry could be a camo-dog.... it does look pretty strong and since Henry is in and out of water (mud, brambles, poop, bracken... you get the idea) all the time it's probably a better bet than a leather one which would be gorgeous but would be knackered in minutes!
They have lots of colours! And look at the sizing chart too as Otto is a medium, but it is a big medium as Otto has a fairly thick neck yet the collar is still loose!
The similar buckles on the ?Rogs? collars cope fine with 30 kg of pure muscle labrador pulling 75kg of person... Collar only comes off when loosened and he backs out - had a bit of a prop forward neck due to stick/tree carrying...
We have ezydog collars for our mad spaniels. They are great as doesn't matter if they go swimming or rooting thro the undergrowth as they are really easy to clean & robust - never had a problem with them coming undone.