I fed their Total Eclipse and other feeds for about six months - my mare lost weight and muscle, had absolutely zilch energy and was depressed. Plus as she is barefoot, they made her footy.
My understanding is that whilst they market their Eclipse products as a balancer on the lines of Top Spec/Blue Chip etc, it does not in fact have the same high vitamin and mineral spec as the market leaders (ie TS/BC). Plus it is Seaweed based, which you have to be careful with because some forms of Seaweed have extremely high iodine content which is not good for horses.
Having said all that, many people feed SS products with success - I just wasn't one of them!
I have been using it since last June alongside their Brewers Yeast - my cob has improved no end - He was bolting, spinning round in the road and spooking at everything but is now much more settled and I can at least reason with him and have not (touches wood quickly!!) had any 'incidents' for ages!
I started him off on the recommended dose and he is now on 1/3 of the dose - has a fab shiny coat too!!! - I like their products cos my boy is molasses/cereal/starch intolerant and there aren't many feeds on the market to suit this. Just to be nosy - why are you wanting to use it?!
I had my lad (see Behaviorist post!!) on the simple system regime, and tried both Lunar Eclipse and Total Eclipse (and also Brewer's Yeast) and to be honest, neither seemed to help with his "problems".