There's a review or two on scope view.
http://scopeviews.co.uk/TakTeegul.htm
I have a Fs60 plus the q extender (FS60Q)!on a Teegul patrol II which works fine. Looking forward to getting the 76DC objective which should be OK as well. Can't recall what the benefit of going to the III was.
The patrol II was Rated for about 3kg but for imaging, you won't get much further than a DSLR plus say a 100 mm lens for around 5 min unguided subs if your drift align is spot on.
No clue about the weight of the FS78 though.
