What if you used cURL, or file_get_contents to DL the files to a folder? Would that be much faster? Then you could parse them by whatever means works best. You have the BASH shell and any number of ways of doing it, that are probably much faster than SimpleXML, even if you just used them to search for relevant files and let SimpleXML do the heavy work, it might save a great deal of time. Plus the shell doesn't have a timeout limit.
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