Hearing many models of Omega speakers over the years, and that includes the 8" Hoyt-Bedfords, I don't recall any major off axis image loss. Dispersion has always been good with any Omega I've heard, even to the point where the image remained intact (like moving around the venue during a live performance and the lead singer remained in their position) even well off center axis. The speaker isn't necessarily always the culprit in a beaming situation. The upline equipment, cabling, speaker positioning, and room acoustics can have huge effect. Where I find the greatest change in image perception is on the desktop where everything is so close and detailed. But on the desktop one won't likely move out of the "sweet spot", so beaming isn't a big issue anyway.
The "6.5 inch" Alnico driver only has an actual active diameter (including surround) of 5-5/8". Pretty small.
The RS5 driver has an active diameter of 4". It's dispersion will not be much better than the Alnico.
Both are capable of throwing not just a deep soundstage, but also a very wide one, extending well beyond the outside of the speakers.
In about four decades of audio, I don't recall a better imaging speaker than the Omegas, nor do I recall ones with better dispersion. YMMV
All the current Omega line, even though they image exceptionally well with good solid state and PP tubes, still image the best with a good single tube per output SET.