Do you want it for mostly colour or B&W and what surface do you prefer?
1290 - Good all rounder but no longevity on the inks. Not great on B&W
(too new to know much about it but I think it will be a step below the 1800)
1800 - Good for colour and works well on Glossy but only one black so OK on B&W
2200 - Excellent for Colour and B&W on Matte papers - good on luster not so good on gloss papers (although pretty good on the new breed of Innova papers) Also good longevity.
2400 - Excellent for Colour and B&W on Matte papers - better than the 2200 on gloss and luster. Also very goog longevity.
3800 - Uses the same inkset as 2400 but bigger catridges and improved perfomance (but you are now in the pro range so the price is much higher)
Not sure about the Canon and HP equivalents.
In the end they are all great printer (yes...including the 1290!) which are capable of producing excellent prints. I have sold prints from my 1290 and 2200.
Good luck with your purchase - and remember to get some good ICC profiles when you have chosen your paper.