Toyota: Sienna AWD and run flat tires

Hi,
I posted a couple questions about run flat tires on the new Sienna AWD a
couple weeks ago, and got some good info in the responses that were
posted -- thanks.
I also decided to ask the questions of Toyota customer service, and thought
that I would pass on the response from them, which I thought was pretty
informative.
My questions, and their response are pasted in below:

----- My Questions:
I am considering purchasing a Sienna AWD minivan, but have some concerns
about run flat tires.

These questions are the result of our need to occasionally take the Sienna
on multi-day gravel road trips in somewhat remote areas (e.g. Yukon's
Dempster Highway).

Questions:
Is special equipment needed to mount/dismount and fix run flat tires?

Are run flat tires the only available tires on the AWD Sienna?

Can conventional tires be substituted on the same rims?
Have changes been made to the AWD Sienna (e.g. suspension) that make in not
advisable to substitute conventional tires?

Is there a readily available conventional tire that can be mounted on the
same rim for use on a temporary basis -- e.g. until you can get to a tire
shop equipped for run flats?

---- Response from Toyota:
The 2004 Sienna all-wheel drive system uses specially designed wheels to
accommodate run-flat tires. These run flat tires do require special tools
and procedures to mount/dismount the tire from the wheel.
Conventional tires can be mounted on the run-flat wheels. This would also
apply if you were to consider using winter-time snow tires on the same
run-flat wheels which would be possible.

However, the contrary is not advisable. You should not mount run-flat tires
on conventional wheels.

Our information indicates that while the suspension and handling are
designed to work well with the AWD system, there should be no adverse effect
of operating your Sienna with all conventional tires, either on the run-flat
or conventional wheels.

As an alternate solution, there is a conventional spare tire and wheel that
can be mounted inside your 2004 Sienna available from your local Toyota
dealership.

We are sure this information will assist you in your Sienna research! We
would be happy to answer any additional questions at any time!!

------- end of Toyota response

Thanks -- Gary

[OOPS! --> Sorry for previous empty post]
Following Gary's inspired example, I sent a query about Sienna AWD wheels to
Toyota, and in only a week got the following reply.
================================================== ===
Subject
Sienna AWD with Conventional Wheels?

Discussion Thread
Response (Sarina) 09/19/2003 02:51 PM
Thank you for contacting Toyota Motor Sales, U.S.A., Inc.
We apologize for the delayed response to your email.

We only recommend run-flat tires for the 2004 Sienna AWD. This vehicle has a
low-tire pressure warning system that is affected by other types of tires.

Your email has been documented at our National Headquarters under file
#200309191042. If we can be of further assistance, please feel free to
contact us.

National Customer Relations

Customer (Nemo Oudeheis) 09/12/2003 02:47 PM
Is there any reason why one could not use conventional 17"
wheels on an '04 Sienna AWD (with OEM run-flats)--say, keeping a set of
Bridgestone Blizzaks mounted and ready for a quick swap-out, should a real
blizzard hit?

"Gary" <net> wrote in message
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