Original Test strings were small (16 chars), the original function was only for 255 although a few of the functions presented have been able to handle far more. So upping it to nearer the 255 limit to see how they cope (so all functions can be run)

IF OBJECT_ID('tempdb..#ProperTest','U') IS NOT NULL

DROP TABLE #ProperTest;

SELECTREPLICATE(STUFF(STUFF(CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65)

+ CHAR(ABS(CHECKSUM(NEWID()))%26+65),N%16+1,1,' '),N%3+1,1,' '),14) AS String

INTO #ProperTest

FROMdbo.GetNums(1,300000);

Results:

Old Method Scalar Function

617393 MilliSeconds

Dohsan

162690 MilliSeconds

Luis

36680 MilliSeconds

Dwain

424590 MilliSeconds

Magoo varchar255

44063 MilliSeconds

Luis V2

49436 MilliSeconds