I’ve been using Lollipop on my Moto G (2014) for around a month now, and so far I really like it. The interface seems much cleaner, especially the notification area (and I do like having a torch in there rather than having a standalone app). The phone does seem a bit quicker and smoother too. I’ve read that other users have problems with 5.0 which should be fixed in 5.1, but I’ve not really had any problems at all.
Apart from this though, there is no real obvious difference when using the phone. I haven’t really noticed any changes to battery life, but I charge it every night anyway and only really drain it after long gaming sessions. I wouldn’t want to go back to KitKat but I would still have been quite happy if Lollipop had not been released, the changes whilst pleasing on the eye are not essential.