Benchmark: timing 100000 iterations of Numeric with Substring, Standard, Standard String Cmp, String Cmp with Substring...
Numeric with Substring:  2 wallclock secs ( 2.47 usr +  0.00 sys =  2.47 CPU) @40502.23/s (n=100000)
Standard:  2 wallclock secs ( 1.59 usr +  0.00 sys =  1.59 CPU) @ 62774.64/s (n=100000)
Standard String Cmp:  2 wallclock secs ( 1.59 usr +  0.00 sys =  1.59 CPU) @ 62735.26/s (n=100000)
String Cmp with Substring:  2 wallclock secs ( 2.31 usr +  0.00 sys =  2.31 CPU) @ 43233.90/s (n=100000)