PHP and XML question

I've recently been doing a lot of work with the google maps API (javascript) and I'm doing some freelance work for a company who needed a cheaper developer. Seeing as I'm not even in high school and have no expenses, I don't cost as much as other developers. For mashups that use an SQL database, I decided that using an XML document that is made out of the SQL data, cached, and destroyed by a php script would be the most efficient way to do this.

Previously I had done work with the domxml extension (My friend suggested I download it when I started learning php bout a year ago, as it doesn't come with PHP 5), but I hate using out-of-date coding. But when I looked at the new XML extensions, apparently I have a choice about which to use.

In your opinions, which extension is best? My criteria for best is: Which covers the most of XML functionality wise? Which is the most frequently updated with quality updates? Which has the largest community/best documentation? Also, if there is an 'industry standard' extension, I would appreciate if you would list that separately even if it isn't the best so that I can get a foundation in it later in case I need it for a job.

Thanks in advanced! :happy::ninja:

Have you looked at SimpleXML?

Ya, SimpleXML is my main contender right now. I was just curious about the others.