All in all I have 40+ Z-Wave devices, so my mesh needs to be handled with care. 
One FLiRS won't hurt, but I can reproduce the effect when only triggering the 3 TRVs in my living-room.
Triggering all 7 TRVs I have will seriously upset the hub.
You'll find some evidence of this in the forums, e.g.
Interesting, but I can only tell from my observations, that sometimes, when triggering my living-room devices at a time, all indicators lighten up almost simultaniously, but only on a good may, mostly one of them gets stuck.
If there's one thing I learned from this forum, that there's a lot special with this protocol.
