The lack of sharp edges compared to the Swarovision bothers me not at all and I dislike the globe effect/rolling ball effect of the Swarovision when panning though I can see it as a possible advantage when grid searching a hill side mounted on a tripod (having the whole FOV in focus and sharp).
To the OP I say try the SLC before you buy the Swarovison.
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If you're susceptible to the rolling ball effect, the 50's seem to minimize it the most.
