If you're after basic steep snow practice, the best bet is Feathertop (very close to buffalo). It offers some nice areas to practice self arrest, snow anchors and your rope systems without being too exposed to the elements (very easy to access shelter via the hut or bail out via bungalow spur back down to harrietville if the weather turns). Not to mention it is also a stunning place to explore in winter!
As mentioned the only catch is you have to walk up there and camp overnight (a great experience in itself imo). The typical access is via Bungalow spur which is an 11km walk uphill and the last few km are well above the snowline. Allow 4 hours to get up to Fed hut.
Buffalo won't really get you much I don't think, unless climbing rock in a freezing environment is your thing!
If you have any questions about the area just ask.