There are basically three sub species of Greys, the largest being the Congo, followed by the Ghana or West African, and lastly, the Timneh.
The Congo African Greys are mainly from the tropical parts of Africa, including Cameroon and the Princeps Islands. They weigh about 400 to 500 grams and are usually light in color.
The Ghana looks much like the Congo, but is a bit smaller and darker. Both have a bright red tail. It is very hard to distinguish between them due to the fact that people have bred Congos with Ghanas for years since their importation. They usually weigh between 300 to 400 grams and are native to West Africa.
The Timnehs are the smallest and darkest in color. They have a lighter upper mandible versus the Congos and Ghanas which have black upper mandibles. They usually weigh under 300 grams and their tails are maroon in color. Most of the importation of these sub species took place between the 80s and 90s. Their lifespan can easily reach 40 to 60 years.
What do you expect from your African Grey? When you bring one home, you expect him to have great talking ability, be a great mimic, be intelligent, sociable, and give you unconditional love and companionship. This is what you want and this is what you can have, but you need to treat your Grey the same when you first get him as you would a year from now. They are highly intelligent creatures who can feel your emotions and sensitivity. They will love you like no other. Most of the time they will love just you, not necessarily the whole family. They bond very strongly to their owner. I will say that in my experience, the Timnehs are a bit more accepting when it comes to strangers. Of course, this has a great deal to do with the way they are socialized.