Aikido vs. whatever- do
Ultimately, it never comes down to a question of styles or Arts, it's a question of the participants' skill. Like in the prior post, I have seen "trained" martial artists lose a fight to "untrained" street fighters. The fact of the matter is that what counts in an actual "realworld" streetfight is the participants' experience, skill, speed and cunning. You will never see an Aikidoka beat a Jujutsuka or vice versa, or a Ninjutska beat a Karatedoka or vice versa, etc., etc. What you WILL see is who is a better FIGHTER, not which one is a "better" Art. To say one Art is better than another is a complete fallacy. You could even imply that a 7th kyu Aikidoka could beat a Kung- fu Sifu, because his Art is "better"; which is, of course, complete bull****.
In the end, this sort of questioning is natural, I guess, and at some point or another everyone either asks the same question or runs across someone who is wondering. Or, what's worse, runs across some unmitigated FOOL, loudly proclaiming that his Art is the only true Budo, and is willing to prove to everyone, hurting himself in the process, or even worse, hurting someone else. (We've had a couple bad experiences on this matter in seminars in our Dojo)
In any case, no Art is better than another. We must keep in mind that every Martial Art is a way to "Stop the Blade", just in different ways one form the other. No which way is "better" than another. All Martial Arts are merely different paths to the same destination: peace, enlightenment, the avoidance of violence as a means to resolve conflict, and a way to be more than what we are: to become sincere, earnest HUMAN people.