I have a Guson Trakrite & they are easy to use, you need a short level clean area to roll the car. If you are going to use a measuring system on the tyre or wheel first spin the wheel to make sure the wheel is true & the tyre is centred. If not true you will get inconsistent readings.
I run my Blockleys at 26psi & rear Nokian Weatherproof at 28psi. I found the original Avons were wearing more in the centre at factory pressure.
