Just for reference:

Tests of FidoNet mail connect time vs. compression method, using the
file "FIDO646.NWS" (FidoNet Newsletter) as a test file.

Included are the actual file transfer times. Times are from modem carrier
detect to carrier loss, plus five second post-connect delay, using
Fido/FidoNet version 12r-bis, at 2400 baud, on a generic 8MHz XT. A
file-attach message was used to transfer the file. 

Compression		size, bytes		total connect time
(NONE)			28 012			2:20
pkarc -oct u foo 	11 640			1:13
lharc u foo		 9 431			1:03

For reference, the connection overhead; the same file-attach message 
as about but without any files. (This is protocol end to end: connect, 
welcome message, transfer, pickup attempt, etc.)

No file			     0			0:20


The file compressed 19% smaller, but performance only improved
only about 14%, due to the fixed 0:20 overhead. Obviously this would
approach 19% if the file were much larger. (If you calculate it as
(1:03 - 0:20) / (1:13 - 0:20) then it comes out to 19%)