These are really neat boats from that era. With the centerboard down they had very good windward performance for a boat of that era. With the board up they had reasonable down wind performance. They were reasonably well constructed and reasonably well finished. Their shortish waterline hurts overall speed a bit and they are not as partial to thrashing through a chop as some of the later designs but were not as bad as the more extreme CCA designs from which the Tartan 34 was derived. There were a couple boom lengths on these boats. The longer boom length and mainsail foot was considered better for cruising purposes. The boom and sail foot were shortened for a better rating in the early days of the IOR racing rules. While they were really good boats for their day, by modern standards they are slow, a little wet and not too great in light air.
Many of these are still tiller steered and are considered preferable to the typical wheel steering installation on these boats, which tends to have a lot of friction, blocks the cockpit and is placed where it is hard to see up the slot.
Still these have always been appealing boats to my eye.