I had a black Ergo from Free Range Kids (they delivered next day with a personalised note too, v good service; think they were new company at the time so hope they are still around). I ADORED it and must have used it for about 2 yrs, in fact I kept it out of attachment and the great, buggy-free memories.
Was easy to put on/ds in, took seconds, no help or faffing required.
Only troubles were these: obviously baby is behind you so if his hat falls off or he needs his nose wiped or anything, you can't really reach.
And, though I have seen people carrying older kids in Ergos my ds, once he got to about 2.5 yrs, was just too heavy, the main strap cut into my belly and almost sliced me in half. However my ds is very heavy set so others might get as much as another year out of it. I ended up needing a buggy for about a year after all (progressed to scooter now!)
People talk to kids a lot more when they are at eye level, ds used to get a heck of a lot of attention when out and about and I think that's really healthy, the buggy-bound are often ignored. Also he could see whatever I was looking at/doing.
Oh another slight problem; difficult to wear a shoulder bag with an Ergo; I prefer wearing bags with long straps, sitting on my hip - virtually impossible. Handbag or even small rucksack worn frontwise is an alternative.
My this is long. But big up the Ergo!
(Tried one of those fancy shawl looking things that you know baby into, about 40 quid or something crazy...needed constant adjustment and was v encumbering.)