[heavenlyhash]

It's really good. I'll vouch for it as someone who has been using the mobile apps on both platforms, and the web application(s) on the desktop for over a year now. They're great. Battery isn't a problem; messages NEVER get lost.

I actually came to matrix after trying to write an XMPP client, believe it or not. The matrix protocol is WAY better equipped for the future than XMPP is: it simply has the core designs necessary to make it federate well and do message sync without losses. (XMPP doesn't. (Unless you count a half-dozen XEPs, none of which are reliably implemented in all clients. But we're getting increasingly parenthetical here; by comparison, matrix Just Works.))

[tacoman]

I've been using Vector/Riot using the Android version in F-Droid on Blackberry 10 for 6-9 months, connecting to my own server on my DSL. I haven't noticed a single issue with battery or lost messages.