I'm the one that's been testing out these new CP's.
The Apex and DX are both very comfortable CPs. I'd say both will stand up to baseball (or softball) impacts without any question. I haven't taken any major impacts yet, but I've had some punches and so forth to try it out and no causes for worry in my opinion. I only work up to Varsity and 18U baseball, so I am only seeing 85-90 top speed, or less, most of the time with rare exceptions.
They both look pretty good under your shirt also. The DX looks very looks natural at the shoulders, no linebacker appearance here. I didn't have to size up for either one of these under my regular umpire shirt, they fit fine under my current shirts. The DX is very thin and offers a much lower profile that rivals F3 v3! The Apex is a bit more round in the chest, think more barrel-chested, but still doesn't make you look any larger than most other CP's (Wilson Gold, Platinum, etc.) out there does.
While I like both of these, I am a bigger fan of the DX. I love the all black design with minimal logo appearance. The neck, wings and belly extension can be removed. I wear it without those on it and it is very comfortable with enough flexibility to be able to throw a ball back to a pitcher.
It is lightweight too. When using my UL harness on it, I forget I have it on sometimes. It's very comfortable to wear. The pad jacket is thin, yet somehow soft and supportive at the same time. It's not hot in Ohio yet, so can't speak to how well it'll do in the heat, but so far it feels like it'll perform every bit as good as any other CP I've had - and I've pretty much had them all except the Power.
My recommendation is to pick up one of these models if you're in the market for a new CP. I am not paid to say that either. I sold all of my other CPs and have been using the DX mostly, but I do like the streamlined appearance of the Apex also. Due to a bit more stand-off, the Apex actually provides more security than the DX - but I'm willing to trade the added safety for a lower profile personally.
I'll try to upload a pic or two once I get home. If there is anything specific you'd like to see, just let me know.