Yeah, I sent a message to a friend of mine whom I have talked to in years to say hello using Allo. Big mistake. It looks like Spam, so that's why I didn't get a reply. LOL
Sigh. Cool things that can't be sent if a user doesn't have Allo should be converted to MMS, and sent as a compressed pic, not a link. I sent my friend a sticker, and it sent her a link to click on to view the sticker.
The problem with Hangouts, is that I can't use it as my default SMS app. I have to use Hangouts for my Google number, and a Messager app (Textra as of now) for my cell number.