I had a major woodie for a longneck banjo (as far as I know these are only bred in the 5-string species) as a youth back in the '60s. they are made to be tuned a couple of steps lower than a standard banjo, and were reputed to be easier to tune to guitar accompaniment. If you wanted to play with "normal" banjos, fiddles etc, you had to capo up about 3 frets. Remember, that capoing up with a 5-string means futzing around with that 5th string seperately. Alas, I found the price of "stretch" banjos to be prohibitive - especially these days, as they are about 30 years out of fasion and getting rather scarce - and settled for a used garden-variety Vega Folk-Ranger which, at $150, didn't seem to be all that bad a deal and meets my banjer-pickin' needs quite sufficiently. The longnecks were a distinctive and often beautifully crafted instrument, well suited to the "folk Revival" era, but I think that only players of considerable virtuosity would realize any significant advantage with one.