I know
I just need a simple straight scope.. but with somewhat quality.
I can get either of them for 1/3 of the 880 or S2 line.
The 660M has better eyepiece it seems. Wider views.
But plastic body.
ED lenses.
S1 HD has narrower eyepiece.
But aluminium body.
APO lenses.
I am leaning towards the 660m because of the wider eyepiece.
Though the plastic body bothers me.
.