I have had experience with three Bianchi mountainbikes locally, and from looking at them I saw that they were offered in different price-ranges depending on the cost of the group the bikes were equipped with just like any other manufacturer's wares.
I think Suntour usually meant a lower-price-range bike, sort of like Shimano STX/LX equipment.
One of the Bianchi's I had my hands on I found at the curb where someone had put it out for trash ten years ago. It was a low-end bike like yours, I wheeled it to my back-yard and someone took it. Next I saw it hanging out of a dumpster behind a business a short distance from my house where the "thief" probably threw it after they found it was not rideable, I just left it there.
A friend of mine bought two high-end, mid-90s Bianchi mountainbikes out of the local Craigslist a few years ago, he picked the pair up for $75, they were all Shimano XT equipped. Unfortunately he was not into them and just stripped the parts off to put on other brand-frames he was more a fan of, a sad end to a pair of unusual bikes.
Always a scarce item and definitely worth preserving since most of them probably ended up in the dump because of idiots like myself and my friend.