Sorry for the old post .... this will be useful for the community though:
If you have IBM Informix 11.70 or greater, you need no commercial ETL as long as you accept to type some query text: Informix now has the so called external tables, that map ascii files ( structured, delimited etc...) or entire directories containing those files, into Informix tables that can be used as regular tables.
This functionality has been implemented from the Informix XPS engine (the previous datawarehouse dedicated version of Informix), meaning it is extremely efficient in terms of performance, sometimes even more than informix high performance loader ( and way more simple to use!). You will find an example in this article
So in your case, copy the files to the other box, create the external tables and then
insert them into the new box's database like this
INSERT INTO new_table SELECT *(or whatever) FROM external_table
And that's it.
If interested in ETL for datawarehouse, check the Informix Warehouse Accelerator solution, which is a revolutionnary way of handling a datawarehouse and datamarts.