Original C Tinwhistle – Black/Gold
Clarke's Original Tinwhistle is still produced essentially the same way as Clarke's first whistle made in 1843. It has a tapered metal bore to bring the finger holes closer together and to increase the range and make the whistle more accurate in the upper registers. The sound is difficult to describe in words, when comparing it to a plastic top whistle most people would say more musical, mellower, a little more character or possibly a less modern sound.

Should you buy a wooden top or a plastic top whistle? My answer is to buy one of each.
They both have their place, the plastic tops are great if you're playing with other people and you don't have a mic and you need that little extra volume and brightness to get your music out. While the wooden tops excel for solos, and for quiet moments when there's just you and your music.