Glasspack Lengths

[4X4Bauer]

I'm looking for a glasspack for my 4.0 explorer. I'm not sure if the full size ~20 inch glasspack will sound deep enough (too much rice?) so I'm debating on getting a shorter, 12 inch glasspack. My only concern with the shorter glasspack would be noise level. I have a secondary cat delete, so would it be unbearably loud? Which glasspack should I choose? Brand doesn't really matter.

 

[FLOffroad]

I've always read that longer glasspacks will yield a deeper tone, so then 12in would be more raspy (and usually more ricey, at least to me).
I think the overly bass-y fart-can/rice exhaust results more from oversized exhaust diameter, not long resonators.

I've been looking into exhaust design for the past couple months, and everywhere I go most intelligent people seem to agree that you can't have too much resonator.

I've heard good things about Vibrant Ultra Quiet Resonators (essentially a fatter glasspack, a normal bottle glasspack will probably be kind of loud considering the 2nd cat delete). They're not very long, but the larger width helps with that.

As a side note, any 'straight-through' muffler (like Magnaflows or Borlas) is essentially a glasspack - the dimensions just differ from the standard bottle-style glasspack.