Since PPMZ uses a lot of memory/CPU its hard to evaluate it on the debian
source packages. Instead it has been evaluated on 29 randomly picked 
(source) packages.

					Size:
FILE:					Tar		PPMd	PPMZ   PPMonstr
libnet-ipnetmember-perl_1.00.orig.tar	30720		5029	5078
popularity-contest_1.3-1.1.tar		51200		9330	9421
liblogfile-rotate-perl_1.04.orig.tar	81920		10254	10120	9660
libroxen-popdrop_1.9.orig.tar		51200		10517	10698
galrey_0.5.4-3.tar			81920		16032	16409
xonix-jahu_1.1.orig			112640		23328	24059
slrnface_2.1.1.orig.tar			102400		23350	23989
chase_0.5.orig.tar			133120		27371	28137
ctklight_0.22.2.orig.tar		153600		30907	31846
libhtml-clean-perl_0.8.orig.tar		204800		37108	38223
lib3ds_1.2.0.orig.tar			788480		93063	97185
devmapper_0.96.07.orig.tar		768000		96455	96595
waili_19990723.orig.tar			665600		103438	107891
cweb_3.64.orig.tar			737280		137835	142537
dvipdfm_0.13.2c.orig.tar		921600		145656	152236
gnome-objc_1.0.40.orig.tar		1648640		166359	169168	
hwdata_0.64.orig.tar			911360		168677	174532
axyftp_0.5.1.orig.tar			2529280		188027	183509	170732
m4_1.4.orig.tar				1239040		211226	220963
zsh30_3.0.8.orig.tar			2375680		437417	457820
chasen_2.2.9.orig.tar			1505280		475422	476336
manpages-fr_0.9.7.orig.tar		5560320		608556	636652
unzip_5.50.orig.tar			4751360		630058	650473
postfix-snap_1.1.11-20021115.orig.tar	6062080		676614	N/A
youbin_3.4.orig.tar			1310720		864727	846722	836893
lg-issue18_6.orig.tar			2877440		1318292 1297317	1287244
scalapack_1.7.orig.tar			31938560	1369437	N/A
torch_2.orig.tar.ppmz			4567040		1675610	1661365 1616614
isdnutils_3.2pre1.orig			15667200	4589378 N/A

PPMZ is indeed very good. It ain't easy to find a compressor that matches so
evenly with PPMd as PPMZ.

PPMd =	    PPMd -o16 -m220
PPMZ =	    ppmz -b
PPMonstr = PPMonster.exe -o16 -m220
N/A = PPMZ can`t compress the file in reasonable time using reasonable amounts 
      of memory. 

PPMonster is an unfree version of PPMd `with time consuming extras`, that has 
been removed from the debian source package to avoid main/unfree mixing 
problems. Its available from: ftp://ftp.elf.stuba.sk/pub/pc/pack

PPMd: 24 wins vs 5 wins for PPMZ.
PPMonster: 29 wins vs 0 wins for PPMZ
