Bicycle Mechanics - Shimano Hyperglide compatability

Does anybody know of any potential compatibility issues with a Shimano Hyperglide Type C freewheel on an older Mailiard hub? Do the hyperglide freewheels interact well with most Shimano componants (I mean, I'm assuming that as they are making freewheels they're compatable with older Shimano SIS type systems).

Just trying to ferret out any issues before I lay out any bucks.

It depends on the model of Mailiard hub. Their freewheels were somewhat unique as they come(quality but different). The Shimano unit is generic enough that it will fit anything with a japanese thread(as most are) and all but 9-spd will be directly compatible chainwise.
If it is a short term replacement, I would say go for it. If you plan on keeping it a while or using it heavily, I would reccomend going a step further and going cassette instead of freewheel. The cassette systems are a load lighter, and easier to service or find parts for. Cost is not so much the issue anymore, as the generic or average level cassette hubs(even prebuilt wheels) are inexpensive.

Well, going cassette would be my preference, but that would require respacing the rear triangle. And/or buying a new frame.

I'm kind of married to the old girl, so doing the best I can to keep 'er going. Oh... and we're talking about 7 speed, right?