Just bought a used Aggie GS212 and ive narrowed it down to three head choices: Aguilar AG 500, GBE 600, or the Thunderfunk 550b. Ive played all three and like them all for different reasons/applications and id like to hear you all's take on them. Which do you prefer? Why? If anyone is interested i play a little of everything: r&b, funk, rock, metal so for my needs versatility is an important factor.