All things being equal, its usually best to do the initial recording in the mode that you intend to use on the final disc (i.e., record in SP if you intend to archive your recording in SP on a disc) because it enables you to do a high speed dub. Why is a high speed dub preferred? Two reasons. First, obviously, its faster. Second, a high speed dub is a pure data transfer so the original recording "data" is undisturbed during the dubbing process. A real time dub requires the original data to be re-encoded, this is true EVEN IF YOU ARE NOT CHANGING THE RECORDING MODE DURING THE DUB (i.e., an SP to SP real time dub is re-encoded). Even if you are real time dubbing from an XP source, the re-encoding will further degrade the PQ vs. recording to the HDD directly in SP, editing, and then doing a speed dub to disc (albeit this degradation is slight, and may not be readily noticeable depending on the nature of the dubbed content - high motion or contrast scenes generally suffer the most degradation upon re-encoding).