Some years ago I used the airport/Plaza Colon express bus and found it to be reasonably priced,with space for luggage, and on a frequent schedule. Is it the same today?
I am unfamiliar with the new metro line to the airport. How far is the station entrance from the international arrivals area?
The regular metro cars are rather narrow and various transfer points to other lines with which I am familiar require a lot of walking and up/down escalator travel. Therefor if you have a large suitcase it might be inconvenient to use the metro to get to the Chamartin Station or the South Bus Station.

I have found the journey on the Metro no trouble and nor did my wife (who was 5 months pregnant on our recent trip) but we had very little luggage. If you have a lot to carry then perhaps the bus or a taxi would be better.
Also, there is a long distance to walk to the Metro from the international arrivals and even though some of this is on moving walkways (which you can't take trolleys onto)it is still a good distance and as you say, there is a bit of walking about when you change trains (although nothing like the London Underground, that I am used to...)
Derek

We, two fifty-somethings, used the metro to the airport fom Sol today, and have to say it was quite easy. We had a small case each and as we travelled mid morning no problems with crowds. A very cheap way to travel!!

------------------

Don't ya'all LOVE the posts from people who are IN MADRID and write to us as they experience things? I do! Thanks, Jude, for reassuring us that the metro is an easy way to go from airport to city! I'm going to try AEROCITY upon arrival in January....