Originally Posted by
dddd
Wharf Rat you're right about the more-upright geometry versus the 210 and 1000 models, makes the bike more fun on the road.
I used mine off-road half the time, I found it was a competent mountain bike, sturdy enough to handle a nuclear blast and with short enough chainstays for good climbing traction on the steepest technical climbs.
Mine came with heavily-scratched top tube sides, I used handlebar finishing tape to cover all that. The rear rack on mine has held up to much hard use and the rack trunk luggage adds enough rearward weight to further help climbing traction off road. I went with a downhill-specific saddle on a suspension post for my many adventures in the Sierra Foothills and on Mt. Tam.
I can't remember if mine ever had the half-step-plus-granny chainrings on it, currently running 28-40-52 with a 14-32t 6s freewheel and indexed levers.
This was my main off-road bike before "gravel bikes" were a thing!

I have a Miyata 1000 as well and very curious to see how different the 610 feels. The stock chainrings on my 610 are 52/46/28, but I plan on switching to 48/36/28 and If I feel the need for more speed, I have a 50t to try out.
I see you replaced your rear derailleur. Was that a preventative move or did the original Mountech actually fail on you? I've read they can collect a lot of grime and are a major pain to service, but work well if maintained?