Which one do you like better and why ?
A quick summary:

My old system used values manually assigned to workunits, which were constant for each workunit type.
For example, it was 5.64 for hxzkv38 series.

The new credit system calculates it's own credits, for most of the results granted values are a bit higher than my defaults (average for hxzkv38 is around 8.5), however for some hosts it's higher than average and for others might be lower, IMO it lacks a bit of fairness, because the work done is always the same.

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M4 Project homepage
M4 Project wiki

I was OK with the old system: do the same work, get the same credit. But I haven't noticed much of a difference either way.

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I like the new system. While the credit bounces around, it is generally about twice the 5.64 old value (on my old AMD machine).
My newer Vista C2D is getting 7.83 (consistent over 2 WUs).

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