I guess we have different ideas of what a "standard" powerhead is. Koralias or their design type basically is standard for any size tank that a non dwarf octopus would be going in.
Maxijets and other smaller powerhead types are pretty useless in larger tanks unless you modify them. They don't produce very strong flow and the flow they do produce is much more directional. Everyone has them in their house and they are useful for other things like premixing saltwater, but I would not put one in a non nano display tank. Even in a nano there are better options these days.
I'm not saying don't use Koralia's but I would not feel comfortable saying they are anything close to the best. If your budget allows I'd recommend going with Tunze's or a higher end brand. You do get what you pay for.
Since the Koralia's have come out I've sent quite a few back to Hydor. I originally bought 3 K4's when they originally came out, one died, another leaked electricity. I've had several of the K4's leak. I basically had my reef tank crash because 2 of the 3 were leaking and I couldn't figure out what was wrong. All of my snails couldn't move in the current and died and polluted the water. They have been somewhat resigned lately, but hydro is not the best brand imo. When one of my friends went to MACNA 2 years ago he brought with him about a dozen of the powerheads and dumped them at the hydro table for them to replace (which they did).
I'm still using 2 of these replaced powerheads in my octopus tank, however they are on my long list of things to one day be replaced. When I heard several people say they are the best, I was quite surprised. They do work, hydro has good customer service, and the price can't be beat unless you go with the really cheap china knock offs, but their failure rate does seem higher then the more expensive brands.
My information may be out of date, as I have no experience with the newer versions of the powerheads, but I just thought I'd share why I don't consider them the best.
btw JMP I love your pics!