Hi Norm and CM,
Put me down for at least one of these transparent caps. I ended up pretty happy with those original CM primer caps. Only bought 2 and both have been great. Probably won't stay transparent will darken over time. I have found the transparent silicone fuel line good. It's just so reassuring to see the bubbles move then stop when you turn on the fuel. I know for sure that I am in for a one pull start.

Funnily there were some aftermarket primer caps that I could see through a bit. They were no good and I ended up returning them to the supplier. Mower would not rev properly and I could see the fuel level dropping in the bowl.The needle was stuck partially closed I suppose.

Jeff