Hello, I had a 988si, 1198 if and an onix if and now a solix SI MEGA.
Solix is really a must for efficiency! nothing comparable on the pleasure boat surveyors market!
I am a fisherman, diver and researcher wreck for recreation, it is a fantastic tool, if you can go directly to solix (the onix and very good too but a little below!) Helix have good performance but lack of connectivity, touch screens which explains the difference in price.
sorry for my english I'm french!!