I picked this bike up a few weeks ago and have been putting a lot of miles on it via gravel, road, trail. Never had heard much about Miyata cross bikes and since produced during the taiwan era, they were never on my radar. But must say this bike is very comfortable for variety of uses. I did add the brooks saddle (sitting around waiting for a build) and the old school bar ends for some alternative hand/wrist positions, some spd pedals and some old tour tires.
While the sportcross was a budget line, I would rather have its solid, though slightly heavy, cromo lugged frame vs aluminum bond of same era. Not designed for steep single track drops but the geometry is fine/great on rolling to flat terrain, I suspect it would make a good tourer as has plenty of room for racks/fenders. So to summarize I find this budget taiwanese cross bike to be a great rider and recommend them if you see one--generally seem to go pretty cheap and good value imo.
