Without a tune the stock air box is really good. I still have questions on whether the fabric filter flows more air than a paper one. The new paper filter on my 2015 GT is huge really deep folds.
Front opening
top view with lid removed
Much better air control on the 2015. Huge rubber gasket closes off the radiators and air box intake to grill opening. At speed there is probably a positive pressure in the airbox this can make a significant difference.
Here's my take based on theory with no practical experience, but after quite a bit of reading.
First there are several factors to consider, some of which have nothing to do with performance, such as:
1. Is the company easy to work with, professional, and responsive.
2. Is the product of high value (good quality at a price appropriate for that level of quality)
As far as performance goes, consider the following:
1. The stock intake is already a "cold air intake", and pulls air from outside the engine compartment. How then do you improve on this.
2. I believe there are three ways improvements can be made. First, you can fit a larger filter element in order to reduce the resistance of the filter itself. Second, you can make the intake tube smoother and larger in order to reduce the resistance of the intake tube. Finally, you can attempt to insulate the intake tube in order to minimize the heat transfer through the intake tube itself.
Note that the temperature effects are most prevalent when stopped and at low engine speeds. When the car is in motion the engine bay will be cooler due to airflow through the radiator. So, depending on your driving, you may not care as much (or at all) about potential temperature issues because they will mostly go away when you are at speed. If you are a road course guy you might not care at all. If you are drag racing, you might care more because your launch might be affected by higher intake temps that could occur while staging.
Based on the above, it seems like all the aftermarket intakes have a larger filter than stock with a smoother, larger diameter tube. I think most get rid of the stock sound tube as well, which IMO really cleans up the engine bay.
The Airraid has a sealed box with a duct going to the stock location. It doesn't look like the tube or box is insulated any more than the stock unit. Should be better than the stock for flow and similar for temps.
The JLT has a box that is "shielded" against the hood, but which has some small leaks around the slot for the tube. Most of the air should come through the stock location, but some may come through the seams around the tube. It looks like it may have an even larger filter than the Airraid. I suspect similar or better flow than the Airraid with the potential for higher temps when stationary.
Again, when moving the temps should not be a concern on any design IMO.
I would probably base most of my decision on how well the company is represented, what their service is like, and how good the product looks under the hood.