[Closed] Fastest way to deadling with XML

I have been using XMLDoeument so far.
My XML size is not that big(usually far less than 1M).

I heard XMLDocument is slow.
I’m thinking about switching to XDocument(Linq2Xml).
I do a lot of in-memory modification and querying of XML and store XML inside of 3dsmax file.

Would it be worth to switch to XDocument?
Any comment on this matter?