By data integrity, I mean:
Checksum was an option, but since the storage format for some data types in MySQL 5.5 has been changed, it won't be reliable.
Another option is to parse the XML file generated by mysqldump. Since the file is too large (in GBs), is it worth it?
Any other way you have confirmed it?
You can use SQLyog-MySQL GUI (Trial) version to compare Schema as well as Data (records) to make sure consistency of schema and data as well.
I solved it by writing a script to get the data dump alone in .txt from both the mysql server machines and did a diff compare. I didn't find much differences except some DECIMAL values where mysql5.5 was clipping values(to the MAX value) in case the value exceeds the size defined for the column. The only problem was that it took some time.
You can check this link to find more details about the above issue here