R/3 4.7 to ECC 6.0 Upgrade - Best Approach?

Hi,

We have to upgrade R/3 4.7 to ECC 6.0

We have to do th DB, Unicode and R/3 upgrade. I want to know what are the best approaches available and what risks are associated iwth each approach.

We have been considering the following approaches (but need to understand the risk for each approach).

1) DB and Unicode in 1st and then R/3 upgrade after 2-3 months

I want to understand that if we have about 700 Include Program changing as part of unicode conversion, how much of the functional testing is required fore this.

2) DB in 1st step and then Unicode and R/3 together after 2-3 months

Does it makes sense to combine Unicode and R/3 as both require similar testing? Is it possible to do it in 1 weekend with minimum downtime. We have about 2 tera bytes of data and will be using 2 systems fdor import and export during unicode conversion

3) DB and R/3 in 1st step and then Unicode much later

We had discussion with SAP and they say there is a disclaimer on not doing Unicode. But I also understand that this disclaimer does not apply if we are on single code page. Can someone please let us know if this is correct and also if doing Unicode later will have any key challenges apart from certain language character not being available.

We are on single code pages 1100 and data base size is about 2 tera bytes

Thanks in advance

Regards

Rahul