Hi

I got a 3 x M5 network last year and it's generally working well, but it's a 3 storey house and coverage could improve a little. I want to add a unit. I have 250/100 Mbit so the M5's work fine, but since most of the bandwidth is used in rooms adjacent to the main unit, I'm tempted to get a stronger unit as master and put the M5's as slaves. What would be a good unit to get? M9 plus?