To reinforce what has already been said, Battendog is about 20 months old now and it's only in the last couple of months I've felt like I am seeing the (almost) adult dog and he has steadied up a bit. Prior to this his behaviour was still pretty demanding and puppyish.
I absolutely believe getting him was the right decision for me because spending time with the dog, training, walking, playing are all things I enjoy and so would choose to spend my time doing them. If I didn't enjoy them it would be a massive ball ache.
In a typical day I must spend something like 3-4 hours dedicated to the dog. 2 x 1 hr walks plus feeding, training, playing, brushing, fussing, toiletting etc. Doing all that means he sleeps or calmly mooches for most of the rest of the time - but if I didn't do it, he would make his own entertainment and it would not be good.
He also restricts what I can do. A day out is a bigger deal because he either comes with me and I have to think about how he will deal with it, will the crowd be too much, how and where can he toilet and drink water etc, what I will do with him if I need to toilet or have a drink etc. Or he stays at home and I have to arrange for someone to take care of him.
If I wasn't already a dog person who tends to enjoy things that dogs enjoy etc, then this massive compromise in my life would really get to me, I think.
In short, the positives only outweigh the negatives IF sharing your life with a different and demanding species is, in itself, a strong positive for you. If you are only in it for the snuggles, then there are a lot of negatives that you will have to deal with, just for a cuddle in the evening, iyswim 