[AS3][Flex] Webservice vs Load XML

Hi,

I’m currently working on a project that contains a lot of data, about 14.000 records. This means an xml file of about 3mb.

Now my question is: Should I use the xml file to load all the data at once, or should I use a webservice, that provides the data when I need it?

Keep in mind that I’m new to webservices…
And if I’m going to use a webservice :
[LIST]
[]How do I store the data, in a mySQL database?
[
]How fast is a webservice? Won’t it take ages to make a call to it everytime I need it?
[*]…?
[/LIST]

Thx, :A+: