I'll admit it: I voted for OOO because he has the best costume, and KamenriderOOO is a cool guy. That was about as deep as I got xD

I only just started Decade. I've seen all of OOO. My decision is probably biased a bit because of that.

Edit: W is pretty awesome, but he's probably more knowledge than power. This is one situation where knowledge does not equal power.

Voting for OOO too. Like matrixbeast said, OOO could easily counter any of decades past rider abilities. Decades complete form can only use finishers/ one attack from the other riders final form, plus he has to keep pressing a button... OOO could easily blind him as RaTorATah, causing him to miss, or freeze him with PuToTyra and finish him off. W... Wouldn't stand a chance =p

Since we have 10 total riders competing in the tourney, whoever gets second place in this battle will be featured in battle 4.

Kamen Rider Similarities Tourney 1, Battle 2- Sometimes Red
 

This time the battle pits the Riders whose main featured forms are red in color.

Kamen Rider Kabuto (2006)

VS

Kamen Rider Den-O (2007)

VS

Kamen Rider Accel (2010, Kamen Rider W)

Lets review their powers and strong points!
Kabuto:

• When first transforming, Zecter can defend Kabuto, Masked form armor can be ejected and cause damage
• Can Clock Up- allowing him to move faster than the eye can see
• Most Powerful Form: Hyper Kabuto
• In Hyper Kabuto form, can hyper clock up, allowing him to move faster than before
• In Hyper Form, can use the Perfect Zecter, allowing him to summon other Zecters to him and utilize their powers for the Maximum Hyper
• Kabuto Extender is his Rider Machine, able to switch from the fast Masked Mode to the offensive-oriented Ex Mode
• Weakness- Requires the Zecter to henshin. If incapacitated, can't transform. Tends to be overconfident at times.

Den-O:

• Has 9 different forms, each with their own skills
• Wields the Den-Gasher, a weapon with multiple weapon configurations
• Can travel through time with the Den-Liner, which has multiple powers in each train car.
• Liner Form is the most powerful form the Rider can take when Imagin are incapacitated, able to use the Den-Kamen sword to communicate with them
• Most Powerful Form: Climax (TV), Super Climax (Movies)
• Climax is a balance of all the Imagin's powers combined, giving him mulitple finishers
• Super Climax allows him to fly, and grants him more power
• Weakness: Can't use other forms if Imagin are incapacitated, can't henshin if Rider Pass is taken from him. Imagin may fight against themselves, causing Den-O to switch forms or lose access to his other forms if their fighting continues.

Accel:

• Has 3 forms (4 counting bike form)
• Wields the Engine Blade, which has 3 different attacks (Jet, Electric, Steam)
• Bike Form allows him to travel without the use of a Rider Machine, can combine with the Gunner A, to use a powerful shot, or a Maximum Drive using the Engine memory
• Most Powerful Form: Trial (TV), Booster (Movies)
• Trial allows him to move at fast speeds, giving him the ability to slash or hit an opponent multiple times in a small amount of time
• Booster allows Accel to fly at fast speeds
• Weakness: Needs Gaia Memories to Henshin, Trial takes away Bike Form and offensive power

Whoever comes in second in this battle will be featured in Battle 4

Who is the more Powerful Rider?

I'm torn. Den-O is my first Rider series(that I'm still yet to complete ._.), but Kabuto's probably the strongest from what I've heard. Hmm...

Kabuto, no contest =p He looks awesome, is faster than both of them (Trial's speed is time limited right?) and can time travel without the use of a train =p

Kabuto can travel through time with the Hyper Zector.
Need I go on? :lol

Anyway, I think you really need to work on your "Weaknesses."
They all boil down to "Can't henshin if they don't have their henshin device."
Mention Kabuto's cockiness, the Imagin's argumentative nature, etc.

I voted, obviously, for Decade.

Of these 3, definitely Kabuto.