Our last dogwalker used to say that he'd found cockers fall into one of two camps - "laidback" and "manic". I think generally for the first few years in my experience they tend to be fairly manic.
We have two cockers, Bella (3 and a bit) and Zorro (20 months). Bella was an only dog until she was almost two years old, and by that stage was turning into a real shuffler around the park, great recall, well behaved in the house, not particularly noisy and pretty good all round I'd say. Then Zorro came along and turned her life upside down and she's now taking his lead as a manic little thing, gets herself in more trouble than he does around the house (she's a dreadful thief, raiding bins, pockets, bags, you name it and looking simply gleeful when caught
). They both bark a fair bit, they both need a fair bit of work to keep their mischievious ways under wraps, but they are the loveliest dogs in my world and I'd not be without them.
I think you have to bear in mind that they are very intelligent dogs, so although they are small and they love to sit on your lap for a cuddle (most of 'em anyway
), they do need mental as well as physical stimulation. My two get an average of an hour and a half in terms of offlead walks each day (usually a bit more in the summer and they're happy to go for much longer walks). They also get training sessions most days and I take them both to agility classes. Cockers are a lovely breed but I would say you do need a fair bit of commitment in terms of putting in their training - they are quite strong willed so you sometimes find yourself battling with those little gorgeous noddles of theirs and I know for a fact that Bella has me completely well trained in the art of handing out sausage when she's walking to heel
I would recommend you do lots of reading on here in all the different sections (particularly puppies and behaviour) as you will get a pretty good feel for them from that.
Good luck whatever you decide!