I know it's an old thread, but it still might be of use.
I use a lovely Snap On analogue gauge. It's quite large, and seems very accurate. I'll slightly over-inflate my tyres at the garage air machine, then use my guage to deflate to the correct pressure.
Not super critical on my LS400, but my (bloody fast) motorbikes and my Cerbera were very fussy about accurate tyre pressure.
It's handy to keep in the boot too, thanks to the case. Some heavy-duty sticky back Velcro, and the case sticks to the carpet lining the boot.
https://store.snapon.com/Dial-Type-Pressure-Gauges-Tire-Gauge-Racing-Blue-Point--P647092.aspx