1/6 or 1/8 wave

I've seen a couple of Intes MK66's advertised - one 1/6 wave and the other
1/8. The 1/8th should be better, but could someone give me an idea of what
the visual difference between 1/6 and 1/8 might be? Is there an obvious
difference in image quality? And would either of these be all that different
from, say, a Celestron or Meade 8" SCT or 7" MAK or even the Orion 150mm
MAK?


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