Avatars may work better (unless animated...
), because they cause less overdraw, i.e. they consume less fillrate. Apart from that, it all comes down to sending batches of geometry data through the pipeline. There is no processing on the polygon level like in the software renderer hence not less sorting of something.
I guess we'll have to wait and see....i hope to release an alpha of the port in a week or so. The Javadocs won't reflect the fact that this thing runs on android now, but i'll correct that later.
Too bad that the technical specifications of the mobile GPUs are pretty much unknown in detail. My educated guess of the vertex performance of the chip in my phone is 200,000 vertices/second at max. The Quake3 demo maxes out at 82500, most likely due to state changes and fill rate limitations. Take your three avatars with 6000 polygons and you might get a frame rate around 10-13 fps, which sounds ok to me for a phone app. However, that doesn't include animations, which will hurt...