Well, it's not a European website, so it's to you to decide if you're fine with it, and use it or not..
However yeah, I don't like it much. Not so much the fact that you can't find your messages all together.. but apparently they are not searchable via search engine either. I tried to google some of my messages within tapas.io and I don't get them. That's a bit concerning. But I'm not very good with this type of research, there may be methods that works. Anyone knows?