I have a Nippon instrument and my experience with it is similar to Michael's. I bought it on eBay for cheap, paid an excellent luthier about $200 to get the most out of it he could (it needed bridge, etc.) and it's a decent enough instrument. It's a little harsh and doesn't have much depth, but it's perfectly good for playing old-time fiddle tunes. It looks like all the other Nippons I've seen.
Then I have a very brown violin that I'm told is a Nippon and it is night and day different from the other one. It has a solid feel and it has a nice mellow tone. It doesn't cut through in a jam but it's a delight to play at home. I've never seen another instrment like it.
If the fiddle you found doesn't need major work--just the basics for set-up--and you have a little money you'd like to spend on it, I'd say go for it! You might find you really like it. :)
And, if you don't, someone else might. I'd take my eBay Nippon over a lot of starter fiddles that would likely sell for about the same.