While any original components may be a bit dated, the Fisher Gemini tandems had an outstanding (but heavy) frame and were well equiped when sold new. In fact, Bicycling Magazine named it one of its "Best of 89".
So, as far as a first tandem goes, it may work out just find.... depending on how you plan to use it and on what expectations you have for the bike. Again, the Gemini tandems are definitely not svelte roadsters and most came with mountain bike components. That said, we have some semi-retired friends who have been riding a slick-tired Gemini for as long as we've known them (6 years?). It's a 45-48lb beast with 7 or perhaps more recently 8 speed components and flat bars. However, they are both quite fit, spin a cadence around 120, and can stay with all of the faster sport/recreational teams on all but the climbs where the bike's heft works against their riding style.
I would put it in the same class as some of the really cool Ibis tandems, Specialized's DejaTwo, Burley's Rock 'n Roll, and other similar 80'-90's 26" wheeled steel enduro tandems, any of which would be a great first tandem for all but the teams who are looking for lightweight racing tandems.