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user_id=6656

On my iBook (600 MHz G3 with 384 megs of RAM, OS X
10.1.5):

L.sort():

 i *sort \sort /sort 3sort +sort ~sort =sort !sort
15  0.19  0.01  0.00  0.20  0.02  0.07  0.01  0.21
16  0.45  0.05  0.04  0.43  0.04  0.15  0.05  0.47
17  1.00  0.09  0.09  1.01  0.09  0.37  0.09  1.08
18  2.16  0.16  0.16  2.26  0.22  0.75  0.18  2.35
19  4.80  0.38  0.36  5.08  0.46  1.45  0.35  5.31
20 10.65  0.79  0.79 11.83  0.89  3.33  0.78 11.88

L.msort():

 i *sort \sort /sort 3sort +sort ~sort =sort !sort
15  0.18  0.02  0.03  0.02  0.03  0.08  0.02  0.04
16  0.43  0.03  0.03  0.04  0.04  0.17  0.04  0.08
17  0.95  0.08  0.09  0.09  0.08  0.34  0.08  0.18
18  2.08  0.18  0.18  0.19  0.18  0.72  0.18  0.37
19  4.59  0.37  0.38  0.39  0.38  1.47  0.36  0.76
20 10.22  0.83  0.76  0.79  0.78  3.04  0.79  1.66

I've run this often enough to believe they're typical
(inc. .msort() beating .sort() on *sort and ~sort by
a small margin).

Looks like an unequivocal win on this box.