The Good and the Bad
Going through the process to unlock Spartan-458 means that you'll be prepared for online battle. You actually do become a better player through the process. On the other hand, with a 6 hour advantage over your friends, you now face a big problem. The older Dead or Alive series were button mashers where overpowerful characters and easily accomplished holds/counters meant that a novice player could still have fun against a skilled player. With Dead or Alive 4, this isn't the case. If you've played through DOA4 and unlocked Spartan-458, your first-time playing friends are not going to stand a chance. In retrospect, this probably reflects the style of Street Fighter II. After all, if you didn't know how to throw that fireball or do the dragon punch, there was little chance that you'd survive. One key difference is that beginners in Street Fighter II could always turn to Dhalsim or E. Honda whereas there's no similar "introductory" character in DOA4. Likewise, back in the era of Street Fighter II, most of you were in elementary or junior high school meaning that spending a lot of time to practice was possible.
Dead or Alive 4 is only a game you can appreciate if you're willing to put in the time. It takes at least 6 hours of game time before you even begin to understand which character you will make your favorite. You’re looking at another 6 hours before you even become a decent player. Of course, it took dozens more hours for us to be good at Street Fighter II…
Online
The online support in Dead or Alive 4 attempts to mimic the arcade scenario. A lot of your time is spent watching other people play as you "wait your turn" in the lobby. This is great in capturing the community feeling but it's a problem when you just want to get in and play. Likewise, although it's theoretically possible to watch battles to learn strategy, things move so quickly that it's hard to learn anything vicariously. You have to play the game to develop skills. Online victories give you an opportunity to expand your lobby and change your avatar as well as help you to purchase new costumes for your characters.