how should I choose a substrate for Power Amplifier design?

[rd_dinesh]

I want to design a power amplifier (at 1.8 GHz and 2.4GHz), i have an RT duriod 6006 substrate(er = 6.45 and Thickness = 2.54mm),
Can i go with this or choose the RT 5880(er = 2.2 and thickness 20mil)?
I saw the latter substrate being widely used for Power amplifier design.

 

[vfone]

At this frequency and medium output power is not necessary to use the expensive Duroid 6006 or RT5880.
The much cheaper RO4003 laminate (1.52mm) will do the job..