Any of the HELIX line is a stable technology ...

There is great advantage is using a SI unit on the console for searching ...and a DI unit at the bow for fishing ...

SI also works well at the bow ...but any dual unit setup can benefit in having one of the units a dedicated DI unit (because the HB SI units do not have a "down pointing" DI piezo) ...

ONIX is cool ... ONIX is very customizable ... ONIX has dedicated DI and SI in the same unit ...ONIX can be buggy like Bob mentioned ...

Rickie