Little differences between OSRIC and AD&D

Let me start out by saying I'm really happy using OSRIC for my AD&D gaming needs - it's solid, well-organized, and the price is right (even for the hardback I just bought.)  This is not a complaint, just something I find interesting.
Every once in a while I notice little differences between OSRIC and the old AD&D books. Right now, I'm in the middle of putting together a good old fashioned mega-dungeon and I'm rolling to stock it (Tables 8-16 on pp160-1 and the Random Encounters on pp 162-8 in OSRIC or Tables V. F-J on p 171 and Appendix C pp 174-9 of the 1e DMG.)

OSRIC

The first tables used, Room Contents are here:

The OSRIC table produces fewer empty rooms, and is more generous w/ treasure.
Depending on how you roll the treasure, you might go to one of two locations (the "Chapter V" is a typo, it should be "Chapter VI".)  The two treasure tables are slightly different from one another, and both differ somewhat from the DMG.
The Stairs results will also be different as the OSRIC table includes more than stairs.

DMG

OSRIC Monster Sub-Table Matrix

I also thought the difference in monster level determination was interesting

DMG Dungeon Random Monster Level Determination Matrix

OSRIC uses a D12 and combines dungeon levels 1 and 2, vs a d20 and combining levels 2 and 3 in the DMG.
Once you get into the monster level tables, you'll see different monsters and different numbers appearing.
OSRIC also states the dice to use for number appearing, e.g. OSRIC states that a roll of 71-75 is 4d10 kobolds, in the DMG a roll of 49-54 is 6-18 kobolds (71-83 is giant rats.)





Like I said above, none of this is a knock against OSRIC, just noticing little differences.