I'm considering making a small bracket to mount this one out on the handle where it's easily accessible. I'll be putting some foam/rubber behind it and loc-tite on the hardware to isolate the tach from some of the vibration and not get loose.

Bringing this thread to life again.
This is so far, the best tach I have bought.

https://www.amazon.com/dp/B00698FFKW/ref=cfb_at_prodpg

My uncle has one on his boat and he has 346 hours on this tach and still working fine. His boat sleeps outside.

He convinced me to buy it for my motor, and I've got 20 hours on it with no complaints whatsoever.
I like that it does multiple things.
Tells the time, rpms, highest rpms last run, hours, and resettable hour meter for maint.
You can also buy the 2 year protection plan, and if anything happens to it, send it back to the company and they replace it no questions asked.

IMO, money well spent.