Thank you Telegix. Where did you purchase your heater? Do you recall the price?

 

I don't remeber. I'm sure a Lexus dealership can order it in without issues.. Maybe 120 bucks?

 

It gets down to -20C often enough in my part of Canada in the winter.

I think your car would start better in cold weather with a battery with high cold cranking amps and properly charged fully. Attach a NOCO GENPRO10X1 onboard charger to your battery, tuck the unit under the panel behind the front right headlight, run the plug through to your front bumper, then you can use a heavy gauge extension cord to keep the car always plugged in. This keeps the battery conditioned and intelligently trickle-charged. The NOCO GENPRO unit can also revive dead batteries using its dead battery recovery/desulphation program, and the unit self-adapts to extreme cold as well as extreme heat.

 

I personally use a CTEK MXS 5.0 to keep my batteries topped up. Its been many years since I sold my LS430 and moved out of Canada. In my current car, has a preheat function which is a separate
module that burns some of your gasoline to heat up the interior. The block heater will help to heat your water up quicker and thus your heating will come on sooner. No substitute for that.