I have been using Google Allo since its launch and I gotta say Google has done a great job on their assistant and I love that It gives me results I am actually looking for.
It’s great for making conversations, also it works as a task manager where you can ask it to remind you something and setting alarms etc.
As a Instant Messaging service it lacks features provided by other services like Whatsapp etc. Whatsapp offers end to end encryption for every chat whereas in Allo you have to start a new incognito chat for E2E encryption. Also it doesn’t let you send files other than just pictures or videos.
It provides you with instant replies during a conversation and also recognises text, images and recommends replies and searches based on what it sees. It also raises a question about privacy though. If you are ok with google reading your every text to make its assistant better than go for it. But if you are not, then it is not for you.