HMC-SDD112 Mounting & Bonding Techniques

Hi,

The Mounting & Bonding section of HMC-SDD112 datasheet recommends to use 5mil or 10mil thick "Alumina Substrate Thin Film" to bring the RF to and from the chip. For my specific application, I want to use a 4mil thick substrtae from Rogers Corporation (RO4450F). I was wondering how that would affect the performance of the die? (Please see the picture below)

Also, I was wondering if I could mount the die directly on the substrate without cutting it, as showing in the picture below:

Thank you in advance for your response!

-Ali