With airpumps though?
External filter wise - yes, they are very reliable, but even then the Eheim branded 'eccos' are no more reliable than the similarly priced competition.
Rena air pumps are reliable (I've had one running for 8 years) and more quiet than at least interpet, tetratec and newair pumps (I compared them for a customer once).
I stopped using my rena because the way I had it set up, the airline was pulling down on the air outlets, and it was on a window receiving direct sunlight, so the outlets kinda melted off. It still works though, and I fixed the outlets easily, I just bought a bigger airpump to use instead.
I've not heard of any experiance with Eheim air pumps, so i would personally go rena. Not that it matters much, but the rena is rated to pump at a slightly higher rate too.