Using fast XML Vendor that implements importNode function

I need to open large XML files (about 10MB). I must use an XML Vendor for TXMLDocument cross Platform. I need to use DOMDocument->importNode function but only ADOM XML v4 supports this function. But this parser is very very slow. Is there a workaround to implements this functionalities in OmniXML (very fast, tiny and cross Platform)? I use C++Builder 10.2 Tokyo Tks   Emanuele