[BioC] Combine dataset from different chip

[Tom]

Some additional information:

My data comes from two different type of microarray: hgu133a and hthgu133a
I want pre-process my data to obtain only one ExpressionSet that contain the
merged data.

What I want to do is:
- merge the two batches with combineAffyBatch function 
- normalize the data (for example with rma)

Is this a good way to pre-process my data?

Any suggest is appreciated. 
Thanks in advance.