while i have never heard a w1 sub(i have heard 10-w3, 10-w6, 10 and 13-w7's), i kind of doubt anyone else will post here, so i will post my own experience:
i started out with some 10" kicker comps--very basic(kickers version of the w1). i upgraded to some kicker 10" cvr's(lets say they compare to the w3--for now). the bass is definitely louder, and punchier, but it still lacks certain notes that i would prefer to have just
as audible as others.
i blame my box-- the box is technically too small-- even for the comps, so it could be that it will not allow the subs to perform to their best-- the audio shop that i bought them from told me that they build all boxes for kicker subs to double whatever kicker recommends, so by that standard, my box is almost 3/4 of what it should be.. but this is about the only box that will fit in my convertible...
to summarize, you might need to try different box designs, or try moving the sub around in the trunk-- sometimes, a certain location will provide less bass then another location.
also, the car audio shops near me have always been more then willing to let me demo subs in my own car-- as long as they have one in a box (they let me demo that boston acoustics oval sub last time--and it is almost as loud as a w7 -- even with my 600 watt sony amp), so it might be worth talking to your local jl dealer to see if they will let you hear a difference.