Here is a rough guide to the E-mu Proteus 2000 series Expansion Sound ROMs.

Information will be updated shortly. Guide prices here to help. Recently a few sellers have attempted to inflate the prices of these part, don't pay over the odds for what you can get for a reasonable price if you wait a little longer.

9062 Pure Phatt ROM
32MEG, 512 Patches of hiphop / rap sounds. Includes some very high quality percussion sounds
and some great basses.
Included with the MO'PHATT module, variations included with the MP-7 command station and MK-6.
The MP-7 rom has KIT presets where the Mo'Phatt versions are BTS presets ready set up for beats mode.
The MK-6 Mo Phatt Keys ROM has 128 extra patches not available anywhere else. This MK-6 rom is
labelled MROM1 as far as I am aware.
 
Target Price: $130 for the regular Pure Phatt ROM. Try not to pay no more than $170 for one of these ROMs.
The MK-6 version may be worth a little more as it is very scarce.
 
9064 ENSONIQ Project ROM
32MEG, Prob 512 Patches.
This extremely rare ROM is very difficult to get, it contains patches originally released by Ensoniq
on  the EXP-1 Real World and EXP-3 Urban Dance expansion boards designed for the ASR-x and ZR series synths.
Quite a mixed range of sounds including urban and world sounds.
 
Target Price: $170, though due to rarity you might have to pay as much as $220 to get one of these in as
new condition with the original box and manuals.
 
9065 Vintage Collection ROM
32MEG 512 Patches.
Originally included with the Vintage Pro module and the Vintage Keys keyboard. Includes a wide selection of
sounds from vintage synth and electronic keyboard instruments. If you want electric piano, organ and synth patches
this may be the ROM you need. This is another pretty rare ROM and is reasonably difficult to find these days.
 
Target Price: $190 if you can find the ROM alone for sale at a LOW price!. A Vintage Pro module could cost as
much as $400 at todays prices.
The Vintage Keys keyboard is very rare these days, no suggested price for that if you can find one.
 

9066 Protean Drum ROM
32MEG 512 Patches.
Originally included with the PX-7 Command station. I dont believe the upgrade ROM was available for long and as
the PX-7 was one of E-mu's last hardware synths this ROM is very scarce.
This ROM is one of the best! has an unbelievable selection of Rhythm sounds, some of the drums are top notch.
The "Cone Ripper" bass patch is brilliant too.

Target Price $170.

9082 Protozoa ROM
16MEG 512 Patches.
Includes 128 patches from each of the Proteus 1,2 and 3 modules from the eighties. Some great sounds in here.
Includes some fabulous electric piano sounds and a variety of world sounds too. The fourth bank is a composite bank of patches
made from samples from all 3 modules. The patch categories and naming scheme is the same as the original Composer ROM.

Target Price $140, this is only a 16 meg ROM and the sounds are available cheaply in the original modules.

9083 Definitive B-3 ROM
Featured in the B-3 Module. Contains mainly Hammond Organ Variant sounds with a few extra patches of other types thrown in.
Captures most useful hammond drawbar settings in this one ROM. If you are big on the Hammond sound this ROM will please you
a lot!

Target Price: $170 This ROM is quite scarce these days. the B3 modules including the ROM fetch some pretty high prices too.

9087 World Expedition ROM
Originally fitted in the PLANET EARTH module. This ROM was sold for quite some time as an upgrade part, it is surprisingly hard
to find these days. A great range of ethnic and world percussion sounds.

Target Price:$170
 

9088 Sounds of the ZR featuring Perfect Piano ROM
Originally fitted in the Ensoniq Halo keyboard. This ROM features a selection of everyday all around sounds, it complements
the composer set quite well. Includes the Perfect Piano patch too.

Target Price: $170
 

9089 X-LEAD ROM
As fitted to the Xtreme Lead 1 module, XL-7 Command Station and XK-6 Xtreme Keys.
This ROM has a few variants! the original 512 patch XL-1 ROM, the X-Lead V2 rom with 640 patches and the XL-7 ROM
from the command station with the first 4 banks of the X-Lead 2. The XK-6 ROM has 640 patches but I am unsure whether
these are the same as the X-Lead 2 in bank 4.

Target Price $115, this is the most readily available and hence lowest cost upgrade ROM. Expect to pay more for a 5 bank variant.
Up to $170 for an XK-6 XROM1 version.

9140 PROTEUS Pop Collection
Included with the Proteus 2500 Module and PK-6 Proteus Keys. This ROM uses the exact same 32 MEG sample set as the
original E-mu COmposer ROM but has an all new set of 640 preset patches. The patch organisation matches the newer
ROMs with all basses under the BAS category rather than BS1, BS2... subcategories like the original.
The Composer ROM has 8 banks giving a full 1024 preset patches!

Target Price $170, has some excellent patches! well worth the extra over the composer ROM for this alone.
Expect to pay $140 to $150 for the original composer rom.
 

9063 Beat Garden ROM
9084 Techno Synth Construction Yard ROM
These 2 ROMS form the sound set for the Orbit 3 Suer Synth. 1024 Rob Papen trademark dance / techno / vintage patches
Probably E-mu's greatest 2 ROM's. These contain a huge range of killer modern synth sounds.

Target Price: $170 each. The Orbit 3 itself is now a $400 item if you are lucky enough to find one!
 
 
9061 Peter Siedlaczek Advanced Orchestra ROM
32 megs of additional orchestral sounds again of the highest quality available on any hardware synth period.

9085 Orchestral Sessions Vol.1 Section Strings ROM
9086 Orchestral Sessions Vol.2 Woodwind, Brass, Percussion, Solo Strings ROM
These two ROMS together were fitted to the Virtuoso 2000 classical module and contain some of the best classical sounds
available on a hardware synth anywhere! of course not as good as new multi gigabyte software libraries but this is
a 128 note hardware system! zero cpu load is worth something right?