I would use TextRectangle or TextBillboard (depending on the requirements). These are the newer classes and I think, they're better. They use the same drawing scheme as the other text components, that I introduced into the project. They should be highly optimized, rendering the whole text on a single texture and single geometry/shape updated on demand.
The Text2D class composes the text of multiple geometries/shapes, one of each glyph. This can be pretty stressing of the scenegraph processors

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Marvin