Main problem as it seems to me is what latest update to DelphiX is based on DirectX7 and it's getting less and lesss support. Even MS fallback implementation of DX7 on DX9 drivers and HW vendor's drivers starting to raise some anomalies with it.
But many people still use DelphiX as easy entry to DirectDraw/Direct3D programming. So, IMHO for hobby programming DelphiX is good library, but for serious one you should look at alternatives.