Drilled or External Overflow?

[gobytron]

Been using the same external overflow for 6 years no.
has never lost siphon and has never caused a flood.

Anyone who thinks that drilled tanks carry any real benefits either have never used a good quality external overflow or they simply did not know how to set it up properly.

It takes up significantly less real estate, is WAY easier to control and clean and you have so many options for placement plus you can always move it when neccessary.