The Solomon Island, Red Sided and VOS are the most common in the US. The Grand Eclectus, which looks like a mini Vos, can also be found.
• Red-sided Eclectus -- Eclectus roratus polychloros (blue eye ring/no yellow on tail)
• Vosmaeri Eclectus -- Eclectus roratus vosmaeri (yellow on tail/no blue eye ring)
• Solomon Island Eclectus -- Eclectus roratus solomonensis (like small Red-sided)
• Aruensis Eclectus -- Eclectus roratus aruensis (larger Red-sided/male has red eyes)
• Macgillivray Eclectus -- Eclectus roratus macgillivrayi (largest, like Red-sided)
• Biaki Eclectus -- Eclectus roratus biaki
• Cornelia's Eclectus -- Eclectus roratus cornelia
• Riedeli's Eclectus -- Eclectus roratus riedeli
• Westermani Eclectus -- Eclectus roratus westermani
generally speaking, the Grand is the smallest and the Macgillivray is the largest ranging in size from about 300g to almost 600g.
As I have only had an Aru Red Sided I can only go on hear say for the others. I have been told the Solomon Island is the most mellow and the Red Sided the most hard headed with the Vos falling in the in the middle. Its not my experiance with Sophie yet but the Aru is said to be the best talker of the Ekkies.
From what I have gathered the "general" assumptions of the sub species is trully vague as it is such an individual bird thing.
The best discription I have seen comes from
Land of Vos - Eclectus Species Profile