The 610 looks to be smaller maybe a 54 or 56? Both are nice scores I would suggest getting them safe (stops and shifts) greasing the stem and seat posts and then riding them, see what you like make sure at least one of them fits. The 1000 is a stunner and very desirable as you can tell from all the drooling comments. I am fortunate to own both a 87 Trek 520 and 87 Nishiki Cresta GT from the golden age of touring bikes but have never had the pleasure of riding a Miyata 1000 or equivalent. Enjoy!