ECU Upgrade

OK, i wanna upgrade my ecu on my 99 lude (i.e. fuel/air ratio, vtec) but i dont wanna spend upwards of $1500 on a upgrade such as the AEM, and Hondata. There's the Venom 400, Greddy E-Manage, Jet V-Force, Apexi VAFC, and the list goes on. Anyway i just wanted to know if anyone could tell me my best bet on an upgrade for $500 or less. If anyone has had any experience with any of these ecu modules, good or bad, let me know. Thanks for any help given.