If I got a reckless driving ticket for $500, is it worth me hiring an attorney?

Yes, you'll still need to show up for the trial, which may or may not be the appearance date on the summons: some courts reach all trials the same day, other trials see if you can settle (i.e. accept a plea) the first day, then schedule a trial for another day if not. You can call the court to see what their standard procedure is.

Your attorney can negotiate with the prosecutor for you, but you'd have to be there to accept the plea--the attorney cannot do that for you. (Or is not supposed to be able to do it for you; I have seen courts bend this rule, however, for minor violations). And the attorney can obviously defend you in trial, but you have to testify--the attorney cannot testify for you. So you should assume that you will likely have to appear, unless you have the option (check the ticket/summons) of simply paying the fine and accepting a guilty plea that way by mail. If that's an option, you'd write your check, check the appropriate box on the summons/ticket, and mail to the court.

As to whether its worth hiring an attorney or worth appearing--that depends how you value your time, money, and any points on your license. Generally, you'll pay $250 - $750 for the lawyer, so if there are no points on the license, you're likely best off just paying the fine. But if there are points, you may choose to hire a lawyer and show up; the lawyer will likely be able to reduce the points, and *may* even get a plea to a no offense, fine-only infraction.