I have both and I'd say that there are distinct advantages to both. The trijicon can not be beaten in durability in terms of mRDS's. it is, in my opinion, the gold standard when it comes to a rough and tumble mRDS. (this is not including an Aimpoint micro, which would take the cake in this category) However, the deltapoint has such a better field of view it is ridiculous. The dot on the RMR is difficult to pick up for fast acquisition at first and with the larger lens surface area of the deltapoint, the dot is much more readily available. That being said it is flimsy in design as compared to the trijicon models. I'm not saying that it is a flimsy optic. I'm saying, comparatively, to the trijicon offerings, it is left wanting in the durability category. I will say that I havent had any problems with either of them when it comes to them working day in and day out and I have them mounted on pistols, not rifles. I would also say that the claim made about the deltapoint's durability is not backed up with a stress or torture test, just looking at it and noticing differences in the design of the models.
All in all, I would say that the Trijicon would be a bullet proof combat grade backup optic and the leupold deltapoint would be a more target or hunting grade optic where convenience and fast acquisition trumps an armored outer body.
Also, I'm not sure which model you are looking for in the trijicon offerings but i went with the new adjustable LED model and have loved it. They allegedly had issues with these models at the beginning of their production but the newer models have corrected the issues they were having with the reticle jostling loose and losing the dot.