The Synta HEQ5 and its Orion Sirius EQ-G are pretty good mounts. I have returned to astro after a 20 year absence and believe me 20 years ago something like the HEQ5 would have cost a bomb.
Its quite a well made bit of kit, some of the engineering is a little strange - the worm adjustment seems overly fiddly and older HEQ5s and EQ6 are reputed to suffer from manufacturing debris left in the mount, poor overall set-up from the factory and the almost legendary block goop which is the grease the factory uses.
My HEQ5 is about a year old and it worked fine and reliably until I upgraded to GoTo when motor bind.stall became an issue so I took the mount to bits.
The killer to the RA axis and the big reason for the motor stall and bind issue was a nasty bit of flaked off metal inside the mount there was also a gritty feel to the lubricant which suggested swarf and general junk in the works. The internal grease wasn't the black goop but seemed like a fairly decent heavy duty auto grease BUT there was nowehere near enough of it inside - the worms were almost dry and the bearings had nowehere near enough grease. At the slow speeds of a non-GoTo mount it was probably adequate - with a GoTo driving the slew at 9x rate the problems obviously came up.
After rebuild and resetting the worm engagement/adjustment the mount definitely runs smoother - prior to rebuild when you moved the mount around manually it always had a kind of 'treacle' feel to it - rubbery almost.
After rebuild regreasing the mount is completely smooth and balancing the scope is far more precise.
Warning though to anyone doing this - the worm adjustment is a complete swine to get right - budget for a fair few hours to be happy with it.
Anyway - thanks for letting me post I'll push off back to my Northern cloudy skies now and just be envious of your undoubted clear southern ones
I am a Dob user, but found your post well written and easy to understand
