Halo 4 engine capabity

Just a Quick question how strong is the Halo 4 engine and how much can it take in Comparison with the Reach engine…

I don’t know about the engine itself, but I heard Halo 4 pretty much pushed the 360 to its limits.
As far as Reach v. Halo 4 … Halo 4 offers stunning visuals but it seems so at the cost of detail. Look closely at a Phantom in H4–even in the campaign–compared to Reach. It looks nearly un-rendered. Which is understandable if the console can’t handle that level of detail and the amazing lighting and scenery. I think (speculation, here) that 343 had to make some sacrifices for what they thought was best. And they did well, I think.
For example, I don’t think the 360 could handle a situation with two Scarabs, Hornets, Banshees, etc (from Halo 3) using the H4 engine. But then again, I don’t know for sure.
The XBox One however … the possibilities. 8Gb of RAM.