Really a big fan of the series, but I'll try to keep this from influencing this review.

DMC4:SE added three very enjoyable characters, costumes and Legendary Dark knight Mode (Legendary DKM mode is only new for console).

Vergil:
+Moves and skills from DMC3:SE and teleporting trick from DmC are mixed with this character along with moves unrelated.
+Three weapons to choose from- Beowulf, Yamato, Force Edge.
+Concentration gauge. Gauge raised by standing still in combat and making hits, losing gauge by missing and running around.
+Teleporting is good for avoiding enemy attacks and is capable of cancelling most moves.
+Summoned Sword and various summoned sword techniques in place of guns.

Trish:
+"Two" weapons- Bare Knuckle and Sword of Sparda. (Bare Knuckle moves are used with "Y" and Sparda used with "B").
+Sword of Sparda is good for crowd controlling enemies, spins around dragging enemies in.
+Bare Knuckle combines lightning effect with powerful melee moves in combination with the Sword's crowd controlling.
+Pandora can be used in Bow, Bazooka, and Laser Cannon mode in place of dual wielded guns. The cannon uses some DT.
-Dual wielded guns are quite weak and cannot be upgraded to charge. However this is not a big issue since Trish is a melee oriented character.

Lady:
+A vastly different character than any brought into the series before. Completely focused around guns.
+Three guns to choose from- "Bazooka, Dual Pistols, Shotgun"
+All of the guns fully charged are insanely powerful. Fully charged shotgun blasts will shred normal enemies and focus down bosses with ease.
+Since Lady lacks melee weapons combos are focused with guns which she uses with the "B" button.
+DT releases a huge grenade blast which gives many invincibility frames along with massive damage to enemies.
-Melee is lacking since the only option is the Bazooka's Bayonete. A "YYY" and "forward Y" aerial attacks, "YYY" and "forward Y" ground attacks. Not much of an issue since you will not normally allow enemies to get close enough for melee to be required.

All characters are strong in their own right however Lady seems to be superior to all new and old characters in terms of firepower and damage output. However Vergil maintains more versatility due to his ability to switch between three weapons.

Costumes:
+Each character gets "EX" costumes which switches their color palette to their oposite character. (Trish swaps with Lady, Vergil swaps Dante, etc.) Obtained in game as a reward.
+Lady gets her old DMC3 costume and Trish gets her Gloria disguise. Obtained through DLC or preorder.
+Characters start out with customization. (Nero gets a skin of his original design, Dante gets a sparda costume and sparda DT, Vergil gets corrupted Vergil.)
+Vergil, Dante, and Nero get Super Costumes allowing them Infinite DT. Obtained through DLC or in game reward.
-Corrupted Vergil costume does not transform him into Nelo Angulus like it does in DMC3:SE. This bothers a few people.

Microtransaction DLC:
Some people make a big deal of this without realizing what it actually is. All this DLC is, is a time saver. Everything outside the Lady/Trish costumes can be achieved quite easily in game. No need to buy any of it unless you want to save a little bit of time.

Cutscenes:
+Vergil, Lady/Trish get opening and ending cutscenes which give them reasons to be where they are. Both ending cutscenes both tease information and are welcomed to the game.
-Vergil, and Lady/Trish do not get replacement cutscenes for story mode. Nero/Dante cutscenes do not even show which some have issues with. These issues do not bother me much, I'm in it more for the gameplay.

Controls:
This game has no mouse support, if you're a fan of the series and have played DMC3:SE and DMC4 on the PC then you'll know this ahead of time. I do not recommend this game to anyone who does not own a Controller. The only reason you should ever buy this game without a controller is if you wish to break every one of your fingers on the keyboard.

Play this with a controller.

Game optimization:
-Missing a few of the optimization options that the original DMC4 had.
-Motion blur and a strange screen effect are quite annoying and impact FPS and performance. Sadly there is no in game option to remove these effects as of the time this review is made. They must be disabled through hex editor, without them the game runs better and has better FPS.
-Some are reporting black screens and being unable to open the game, devs are looking into this but no fix as of this review.
-Performance seems to vary, the majority report that the game works fine while there is a minority who cannot seem to run the game very well. Check your specs before you purchase however the slightly worse optimization compared to the original may be at fault. Hopefully devs are looking into fixing optimization problems.
-For some reason FPS is slightly lower than the original. I assume this is due to the poor optimization.

Overall:
If you enjoyed the other DMC games (1,3,original 4) then you will assuredly enjoy this game. There are those that believe $25 is too much for a "re-release" of a game that they may or may not already own. However the price is fine for the amount of content they have added. On average when compared to other games the addition of 3 characters and 2 new game modes will cost more than 25$ along with the cost of the original game. Optimization is hopefully an issue that developers will fix however as of this review they have not.

I would have given this game a 10/10 however do to the optimization issues I will have to lower my score to 8/10. An extremely good game that will have to settle for a lower score until the optimization issues are cleared up.