If you want to record 2 shows at one time off DirecTV, you can only do that with a DirecTiVo or Microsoft UltimateTV. Replay (like stand-alone TiVo) only has one tuner, so only one show can be recorded at a time.

DirecTiVo and UltimateTV save the DirecTV data streem to the hard drive instead of encoding the signal itself. Because of this, there is no picture degradation. BestBuy locations are selling Ultimate for $49. DirecTiVo is currently being redesigned and will not be back on the market until Thanksgiving as DirecTiVo Series II. Series I units are still available some places, but I would wait for Series II.