Blending with different formats

If I have a normal color buffer set up as RGB (24bit) and a texture defined as RGBA (32bit) and perform a blend with the func:

glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

Will this work ok?

You do not say want you want to achieve, but for standard transparency it will work.

The source is the texture (RGBA), the destination the framebuffer (RGB), so as you work with SRC_APLHA, there should be not problem.