They aren't really rubbish or a waste of money. They do what they do pretty well, any piggyback is pretty limited. Yeh a standalone is better but for most people pointless and OTT for their setup. There isn't much competion for EMB until the ecumaster popped up. They are flawed as cannot fully get away from the stand ecu. However mapped properly do well. Theres a guy who has over twice standard power on his 1l turbo car and does 24hr endurance races with no issues on a EMB