This message was posted on behalf of Intel Corporation
Thank you for contacting us, let us try to help you with your questions.
The difference between both kits is that the $99 kit is manufactured by Intel and has limited shipping to a few countries (USA, Canada, China, EU and Japan). The the $169 kit is manufactured by Creative and the RGB sensor is better; it also ships to more countries.
Between the R200 and the SR300, the SR300 is definitely the one we recommend for Face Scanning. Regarding the resolution, you could try to change the Reconstruction options (ReconstructionOption) to see if you get different results, there are four options available, NONE, SOLIDIFICATION, TEXTURE and LANDMARKS. Hopefully this will provide better results.