The only major difference between Essentials, RHall and Complete is the number of algorithms you get in each product.
LX480 RHall is the most simple and straightforward product, and includes 3 basic yet important features: the legendary Random Hall algorithm, the enhanced version called Random Hall HD, and Dual Delay. You can try the demo here.
LX480 Essentials is a streamlined version of the LX480 Complete, offering four of the most famous presets (“Plate,” “Ambience,” “Hall,” and “Room”) from the original and with specific parameter controls. It also includes signature presets created by 6-time Grammy winner Richard Furch and 8-time Grammy nominee Joe Carrell.
LX480 Complete is the most comprehensive collection of recreated algorithms from the classic Lexicon 480L offered by Relab. It’s a digital one-stop-shop for Lexicon lovers, and includes the following algorithms: Hall, Plate/Room, Dual Delay, Panorama, Random Hall, Random Hall HD (Enhanced Version) and Ambience. You can get a FREE TRIAL here.
Which one you choose will ultimately depend on your needs and your budget.