I personally like my Erica Dual FX. This is the only FX module I’ve owned so I don’t have anything to compare it to or suggest something better. It’s worth checking out, though!
-- Avesta
Actually, it's two FX Aids under one panel.
Many synth companies use this multieffects chip known as the Spin FV-1. They're easy to work with and they can do plenty of algorithms...but they all sound about the same. Even my AE system has a stereo FV-1 module. But the neat thing here is that this sure doesn't COST like an FX Aid XL; two of those would be about $500-ish, while the Erica comes in at around $200 lower. However, the FX Aid XL has multiple CV ins for parameter control, while the Erica's implementation is more like the regular FX Aid. Still, you come out $100+ ahead with the Erica. Decent choice!