What speakers for horizontal tri-amp configuration

What speakers are recommended for a horizontal tri-amp configuration? Assume 3 external tube amps (150W ea.) using the passive crossovers included in the recommended speakers. Speakers need to have 3 sets of posts (Bass, Tweeter, Mid).

I have seen sonic benefits from horizontal bi-amping. I also enjoy the flexibility in tube rolling to match the amp to the speaker being driven (tweeter, mid, bass).
I have a pair of Tyler Acoustic Woodmere II's that have that configuration...I am only using two sets of posts and jumping the third...
I love em...They are truly a marvelous speaker...I have a VERY LARGE room and they fill it up nicely...esp the sweet spot..If you are looking for something TY will hook you up with any custom configuration you throw at him..