I applied the Peel & Stick product from Lowe's several years ago on my 85 hardtop Vanagon.  On the front floor, up under the dash a little (basically wherever there was carpet), front wheel boxes, inside both front door panels.  Yes, it DOES make a difference.  Not a huge one though.  I'd estimate something like a 25-30% reduction....very difficult to quantify.  No, not a Lexus.  I think I used 3 rolls, can't remember the length (15'?) but was 6" width; cost I think was around $35-40 or so.  Once you put it on...it's ON!  Just cut with a utility knife, slap it on, overlap here and there.   No issues with asphalt smell, ever.  And just this weekend I was in the Southern California deserts with 94 temps, have been a lot hotter over 110.  I've forgotten all about it, so maybe that's a good sign.  I'm glad I did it, only took a few hours.

Rich
San Diego

--- On Sun, 4/29/12, Jim Felder <jim.felder@GMAIL.COM> wrote:

From: Jim Felder <jim.felder@GMAIL.COM>
Subject: Question about sound-deadening alternatives
To: vanagon@GERRY.VANAGON.COM
Date: Sunday, April 29, 2012, 3:51 PM

Alternative for lack of a better word—meaning an alternative to the
expensive products made for the purpose, that I have to order and
can't get more of if I run out.

Over the years I have heard people refer to a peel and stick
asphalt-based product they got at the home stores. I was poking around
today and found various sizes of rolls of peel and stick flashing. I
was not impressed with how thin it was.

Is this what people are using? Is there another product I should be
looking for? Is it just not worth it, and I should be ordering the
real deal?

Those with opinions, please share.

Jim