Dear Tamer,

The information is insufficient to make any suggestions. The 'new process' needs elaboration. The objective of the study needs to be stated.

Regards.

Multples case designs may involve three main variations:

1. different contexts for each case using a single unit of analysis,

2.different embedded cases indifferent contexts involving more than one unit of analysis,

3. Multiple cases analysed within the same context. For example carrying out research on the imitative behaviour of banks within the retail banking sector. In this case, the context is the banking sector which common to al banks. 

The objective of the study and the research question it tends to answer to justify if the same context or/and different environment will be appropriate. It is all about justification that resonate with the problem to be solved by your study. It can be either way.

Your evaluation will only be as adequate as your trial basis and, given the number of factors involved, if the base is simply two case studies, it might be more useful to have different settings and environments. Presumably your new development process seeks to improve on certain factors compared with others. If this is correct then use your hypotheses in creating an improved process as a framework for the evaluation. This means rigorously testing the specific factors that differ from competing processes. However, using just two case studies is a very small study and unlikely to be very convincing unless the improvement is substantial and/or the case stuides highly representative or significant in some way/s.

Different settings if conducted simultaneously; same settings if conducted at different times, etc.

It is esential to link your case study to theoretical propositions. Having different contexts may or may not influence the production of evidence. But this is the question to ask in the light of further information you certainly have.

Actually it depends how you are placing your objectives.. if it is just informative then probably you can go with this.. otherwise some more data is needed to have a clear cut strategy.. 

The decision on which context to use and how many cases shoul dbe guided by the research question, but also what the unit iof analysis is. Defining what the case is, teh boundaries of the case and what about this needs to be understood should then inform the selection of site and case(s).

All that is said, objectives, questions, design of the study, are important. however, when you talk about the development model, and multiple case study in a in a similar or different contexts, important is to specify what do you mean by the context. for instance: cultural, developmental (developing/developed), temporal context, ttheoretical context, or subject area. for an explanation of the context see Siman, 2015 that deals with the question of generalization from a single ccase study. secondly, why you are concerned about the context, in order to generalize? in order to make your model more far reaching? or have any other objective you have  in mind that is specific to qualiitaative research (apart from the specific objectives of your research). see Yin, 2015) for who talks about generalization from multiple cases. in published in a journal named Evaluation. the issue is a special issue on ccase study.  though not related directly  to your question, however, development, evaluation, multiple case study, context, case study, and generalization are the key words. If any further query, you can email me, because I am now a days engaged in writing a paper on case-study generalization in varying context, but by context  I mean, spatial  and culturaal context.

context indeed matters, when we talk about development, therefore it is very important that you should be very clear about the type of context that you are concerned with

Hope it helps.

You ned to think about the kind of evidence that you would produce through each of your two possible approaches, and how that evidence would matter to the audiences you want to convince. One the hand, some people might be more convinced by showing that you predictions work best in two similar but separate cases. On the other hand, other people might be more convinced by showing that your predictions can apply in two different contexts. Which of those situations is more likely to characterize the audiences that matter to you?

In my own case, what would impress me the most is if you not only worked with two different contexts but not also made successful predictions about how your process would operate in each of those contexts. In other words, don't assume that your process works equally well across all contexts; instead, show me that you understand how your process will differ from one context to the next.

OK, very difficult to respond, given the paucity of information, but my approach in my research tends to be cross-confirmation (or otherwise) in similar situations, followed by consideration in a different situation for veracity (or otherwise) there. In my case "different" = different by geographic location (and "similar" has the same locus), though, of course, there are other possibilities, such as temporal.