No opinion on the submarineability of either setup, but I took a k&n fipk off of my ford truck, an application where it actually helps power, because the sound level was obnoxious. Anything above 1/4 throttle and it drones so bad we had to yell in the cab. No more thought goes into those things than the homemade setups that a lot of guys do, but they cost a lot more. Junk, imo.
Some sort of cowl induction is the right answer. Cool air, from a higher point that's visible to the driver.
If you want to test if your factory box is restrictive, unbolt the box from the inner fender and reassemble the box, then rev it and watch the flex pipe collapse and expand with every rev no matter if it's 2000 rpm or 5000.
94 jz, bruiser, la, cage,5.3 ls, 36 swampers 98 jz, the mutt, 3.5 iro, 33 swampers, avalanche conversion, 02 north face avalanche blacked out work truck, 06 rhino R1 engine, 4x4, Leeroy's custom paint, 04 escalade wifes truck 22s, 03 duramax 18s, completely blacked out, efilive by nick, wicked wicked truck, 39 chop chevy rod, aluminum 5.3 ls, 08 apex, 310hp mcx turbo, holz 162, completely black, CCM built.
I put one of those on, took it off after less than a week. No noticeable power difference, and it howled like a scalded dog. I go off road to commune with nature, not scare the $%# out of it. Stock system seems to work just fine.
Indeed the noise is very intrusive, cool when you're messing around on your own but can be a little embarrassing when you give it some throttle carrying the inlaws around.