Dear Icar,

Though i dnt consider myself a pro but i would like to share my experience with you. With simulation and actual designing, the basic purpose is to assess the actual need and requirements of a plant with an overdesign/safety margin usually of 10%. You are right. Different property packages would indicate slightly different values because each package has a certain and specific thermodynamic property running in the background. With gases, we all know that at high pressure their behavior is somewhat erractic as compared with ideal circumstances. Now you have two scenarios. If i were you, i would go with the PR as it gives the maximum value plus that the HYSYS recommends using PR for TEG Dehydration. I recently attended a course by HYSYS where i came to know this. "Dnt know why then they created Glycol Package but their must be obvious reasons that i dnt know off".
Further for assurance purposes, i would recommend going through API Spec 12 GDU. As TEG based units are not complex, the standard enlists methods that can be utilized for exact determination of plant size alongwith circulation requirements. Add little bit of industrial experience to it and Voila!! You'll have your own designed TEG unit ready to rumble.