on my machine, these are the results of the benchmarking:

Benchmark: timing 500000 iterations of Clone, Storable...
     Clone:  4 wallclock secs ( 3.27 usr +  0.00 sys =  3.27 CPU) @ 15
+2905.20/s (n=500000)
  Storable: 30 wallclock secs (29.52 usr +  0.01 sys = 29.53 CPU) @ 16
+931.93/s (n=500000)
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(... is a Pentium 4, 3GHz (cache 2MB) and 1GB of RAM) ...

Seems that Storable is a little bit slowler than Clone. But, on the other hand, i didn't have to install it ... seems to be at the main perl distrib ...