> - temperatures it can maintain inside at various diff. temps outside

Don't have any actual data for you other than it works well down below
freezing (20-30 below).  cab temp is at the point where a t-shirt and
thin fleece jacket are comfortable!

> - whether it heats the pop top area at all

When its 20-30 below openning the pop top IS NOT an option whatever
heater your using.

> - how does the aux battery hold up under heavy use (when it's 15-20
> degrees out)

Fine, and mine is just a regular Vanagon vented battery under the
drivers seat.

> - what is maximum time re continuous use before battery is drawn down

I've left my Westie parked for 2 days with the heater left on with the
thermostat set to the minimum position (an effort to stop the water tank
from freezing) with no battery problems.  Don't forget, the heater is
only on for a short time each hour.

> - are you glad you got it

Best thing in the van!

> - reliability/malfunctions/maitenance

Perfect, flawless.  This is my 5th season with my compact 1600, you can
get much bigger units too - even a deisel powered unit.

> - do you regret loss of under seat space

No, I fabricated a wire closet type shelf above the propex.  Now I keep
all my canned food stuff on the shelf - enough space for a weeks food on
the road.

If you have no problem spending the money for the propex get one, and
make sure to fit the aux. battery too.  Switch all the camping gear over
to aux. battery also, you'll have a great set up.  Propex units are a
real "no brainer".  The toughest part is getting one!

BTW.  Never had a problem with the propane freezing, I'm told this only
becomes a problem around 70 below.

Maybe Kyle can get a shipload (trade price from the UK) and sell them
retail in the US.

Regards,
Chris Gibbs.  Eagle River, Alaska.
1988 Propex powered Wesie