both will fit just fine. the regular ones have minutely larger surface area on the cone due to the shape of it being "deeper" but thats about it. the regula ones will handle a bit more power too.
you can fit either in the front and rear doors just fine. the shallow mounts are more expensive because people dont have a choice to use the regular ones if they need a shallow tweeter mount on the speaker. this is generally only true for the people that sell below MAP or MSRP as polk says that they are both 99 bucks.
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