I used to have a Sienna too with AWD the Runflats did not last and were pretty bad. I replaced them with regular tires and purchased a spare a spare tire and wheel for less than the cost of 4 RunFlats.
I am now looking at new tires for my CMAX and am a bit torn.
Pirelli cinturato p7 all season plus
or BRIDGESTONE ECOPIAEP422 PLUS
CINTURATO P7 ALL SEASON RUN Flat
They show as weighing 26 lbs which seems to be be standard the Bridgestone Driveguard show 29 lbs.
There is really no place to have a spare in a CMAX and while I can fix a small puncture I also know that sometimes you cannot plug a hole. I used my Runflats a few times on the Sienna when I first owned it finding nails like the car had magnets on the tires to attract nails.
CINTURATO P7 ALL SEASON RUN FLAT -