Speakers free of grain, glare and steel?

The Fritz are monitors it appears. The Other two are more full range,if that matters.

The kind of amp used will make a difference between the two full range Merlin and OHMs.

I suspect the MErlins will shine with tube or lower power SS amps. The OHMs may do quite well with those, you'd have to try and see/hear, but require high current SS amps to achieve their potential.

Some report excellent results using a sub with smaller OHMs run off tube amplification.

Which will integrate into your room and listening location best is another consideration. The OHMs will provide a large sweet spot for listening. The others will likely have a smaller sweet spot.

From there, I think its mostly a matter of personal preferences that are harder to assess that will be the remaining determining factors.

Proac?

The Merlin TSM MMI and Fritz Carbon 7 are monitors, the Ohm floostanding.

Are any of the various suggestions noted for their efficiency?

Pmboyd,
What will you be driving said spealers with?
As noted above electronics on the front end do have an effect on the speaker end.
As with speakers, all amps and sources are not alike.
If I missed that info from a previous post, my apologies.
Chris