EDI beginners question

Hi All,

I am very new to BizTalk / EDI development and needs some guidence / best practices to start the project. Currently I am involved in integrating EDI 850, which is sent by our 6 vendors. All 6 vendors have different implementation of 850 standard. I am thinking of following 2 options, please let me know your thoughts.

Option 1:
1. Create vendor specific schemas for all 6 parties.
2. Create 6 maps to convert vendor specific schema to common schema.
3. Create 6 Orchestration which has filter set to ISA06 = <their partner id>.
4. Above Orchestration will apply vendor specific map and call Common Business Orchestration, which does all the work.

Option 2: (I don’t know its possible with BizTalk)
1. Somehow create Common 850 schema (Untyped message)
2. Create Orchestration, which will apply map (vendor specific) dynamically by reading ISA06 element to convert to common schema.
3. Then call Common Business Orchestration, which does all the work.

Option 2 looks great which allows me to add new vendors without much work. But the problem is, I can’t create vendor specific map using Untyped message. I am open to other suggestion as well.

Please also let me know of any links, resources or best practices to implement BizTalk solutions specially EDI.

Thanks in advance for your time.

Regards,
-Javed