The nice 4 probe CHTs (the only ones worth buying) can be a little pricy... but for knowledge on how your engine is doing, it's a small sacrifice.

Jeff Hersom
N3740J '67 150G "Gremlin"
N8634S ‘66 150F/150hp “Rusty”
Hangar W-6, Helena Regional Airport
Places I have landed Gremlin:
[Linked Image from visitedstatesmap.com][Linked Image]