Carbtune is what I have and it is convenient. You don't have to worry about ingesting the rods into the engine when you wack the throttle closed too fast, but I think it is slightly less sensitive (and less accurate) as compared to one of the liquid types.
Lots of folks make their own 4 channel manometer using ATF in the tubes. Because of the light weight of the fluid you need to make it fairly tall, but that also increases the precision of the gauge. If you'll always only be using it in your own garage, and portability is of no consequence, that is probably the best way to go.