I had the MGEN 2 and it was very easy to use and effective. Now I have the MGEN 3 and it's even easier to use and guiding is on multiple stars rather than just one - you literally turn it on, press one button and within a couple of minutes it's autoguiding.
The MGEN controls my Nikon DSLR's and dithers - couldn't be simpler, but could be cheaper
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