Welcome to the forums.
Im not a super wiz with RSLinx, but this question about EDS has come up in the past (not on the Forums), so here is my understanding.....
The EDS (Electronic Data Sheet) is primarily for fixed function devices. Things like Drives or a fixed digital input module. They can only do one thing and thus have a fixed 'register set'.
The EDS for them can thus be really well defined and locked down, thus making the importing of all those 'register sets' easier with an EDS.
The R2 is a 'reconfigurable' device. You can change where different modules plug into the rack, you can change the function of some of the modules. For example, analog inputs could be linked to PID loops (or not). Digital outputs could be TPO outputs (or not).
In other words, the R2 is a dynamic module and the EDS can not account for this.
My understanding is that the EDS does not contribute any functionally to RSLinx, so its usefulness in this role is limited.
Our EIP_Configurator provides the means to define assembly instances and these can be brought into your system easily.
That's about the sum total of my knowledge on EDS's.
If you have any other questions that need to be answered 'quick', then please email email@example.com.... Other wise, just keep an eye on this post here and see if we pick up any other replies.