First of all, Welcome.
To answer your question, it's best to say that Spider models are desirable based on the opinion of the enthusiast. Here's how I would break it down if you were to ask me.
1966-1969 - These spiders are known as boat-tails or Duettos and are distinguished by their rounded-off rear-ends. They are among the most desirable Alfa Spiders. They are rare and good examples are expensive.
1970-1974 - Known as Kamm Tails. They are light and because they came out before the United States employed strict safety and emission laws they are the among the best performers of any Alfa Spider. You can still find very good bargains for good Alfas in this category. But I think it's only a matter before that changes.
1975-1981 - These are the ones that I would try to avoid. They have ugly rubber bumpers on both ends and are relatively heavy. This means they are not performers. They don't really demand a lot of money from those who are trying to sell them. They can be nice and there are those who like them...but that's not me.
1982-1990 - Lots of good deals here...but you either love them or hate them. They are distinguished by a small spoiler that came stock and are the most aggressive looking cars of the run. They are very good performers but the design keeps some enthusiasts away. 1990 is often the model year of choice out of this category.
1991-1994 - Known by enthusiasts as S4's they are the forth and final series of Alfas to be released in North America. They are distinguished by fully integrated color-matching bumpers. They have a very smooth and elegant appearance overall. These are the only Spiders in the states that came with power steering and driver-side airbags. They are popular cars but not always easy to find. Performance is good but these are also the heaviest Spiders around. Clean examples with lower miles usually cost around $12K+.
The S4 and Duetto are my overall favorites by the way. For what your looking for however, I would suggest finding an Alfa made between 1970-1974 or 1982-1990.
More detailed info can be found here:
http://spiderfaq.home.att.net/dev_his.htm
To answer your question, it's best to say that Spider models are desirable based on the opinion of the enthusiast. Here's how I would break it down if you were to ask me.
1966-1969 - These spiders are known as boat-tails or Duettos and are distinguished by their rounded-off rear-ends. They are among the most desirable Alfa Spiders. They are rare and good examples are expensive.
1970-1974 - Known as Kamm Tails. They are light and because they came out before the United States employed strict safety and emission laws they are the among the best performers of any Alfa Spider. You can still find very good bargains for good Alfas in this category. But I think it's only a matter before that changes.
1975-1981 - These are the ones that I would try to avoid. They have ugly rubber bumpers on both ends and are relatively heavy. This means they are not performers. They don't really demand a lot of money from those who are trying to sell them. They can be nice and there are those who like them...but that's not me.
1982-1990 - Lots of good deals here...but you either love them or hate them. They are distinguished by a small spoiler that came stock and are the most aggressive looking cars of the run. They are very good performers but the design keeps some enthusiasts away. 1990 is often the model year of choice out of this category.
1991-1994 - Known by enthusiasts as S4's they are the forth and final series of Alfas to be released in North America. They are distinguished by fully integrated color-matching bumpers. They have a very smooth and elegant appearance overall. These are the only Spiders in the states that came with power steering and driver-side airbags. They are popular cars but not always easy to find. Performance is good but these are also the heaviest Spiders around. Clean examples with lower miles usually cost around $12K+.
The S4 and Duetto are my overall favorites by the way. For what your looking for however, I would suggest finding an Alfa made between 1970-1974 or 1982-1990.
More detailed info can be found here:
http://spiderfaq.home.att.net/dev_his.htm