First off I would like thank Chris Dias for finally getting this book out, its been a long wait but it's so worth it!
Ultramodern4 (UM4) is the latest supplement from Dias Ex Machina, taking the next logical step beyond it's previous Amethyst setting and bringing more generic modern rules to the table.
The biggest changes from your standard D&D or amethyst game is the new class/ladder system.
Classes are a bit lighter in weight, they have fewer powers in general but still are the "What you do" of the game. They are a bit more generic with names like: Faceman, Heavy, Mastermind, Specialist. Anyone familiar with Amethyst will probably recognize a fair share of the mechanics, the sniper uses the marksmen talent from the stalker sniper for instance.
While classes are a bit pared down from what you would be used to it's because of the Ladder mechanic. Ladders are the other side of the coin, they are "How you do it". While you might be a sniper, you could be a Juggernaut Sniper, replacing your usual reliance on DEX for powers with CON. You could be a Savant Gunslinger, using your keen intellect to take your foes down.
Overall I love the mechanic, it really opens up more themes, letting more then one type of person be locked into a class.
Paragon paths and epic destinies like most items in this book are also fairly generic, with 22 paragon paths such as: Driver, Field Sniper and Cinematic Cliche and 5 Epic destinies like: Ultimate or Respected. you should have no problem bringing your character into the higher levels with some great mechanics and flavor.
Skill and feats, some of these are revised or updated versions of Amethyst rules, notable vehicle operation and demolitions, but with expanded sections in some of the skills such as sabotage under engineer there is plenty added for any game you'll run. Also included are contacts, which can be purchased or received with feats, these characters are pulled right out of an action movie, they are the people the hero always contacts for that helpful bit of information or to find some kind of black market object or occasionally showing up as added backup.
Weapons and equipment, For me this is the real meat of the book, there are items in here for every level of tech you might want. Everything from revolvers to plasma cannons, Ballistics Armor to XH Dragon powered armor. This book has it.
Another aspect I liked about the equipment is that everything has a price and a loadout value, loadout being rules for adventurers who might be a part of an organization or other kind of group where they wouldn't necessarily buy all of their equipment. it lets you set a loadout value per adventure with modifiers depending on intelligence and a few other items and lets the characters requisition equipment. Perfect for a military game.
included in the book as well are two adventures and a great resource with its Adversaries chapter, giving you a lot of basic bad guys with great trait templates.
Overall I have to give this product a thumbs up, its quality is not only in its content but its layout as well, I personally have not had many 4e 3rd party products with the production quality that DEM puts in its products.
If I were to place one complaint, it would be that the class layout is a bit of a jumble, no clear definitions between classes, they just flow into each other. But its a minor nitpick.
If you are looking for the perfect 4e modern rules, they are right here.