looking to buy a scan tool. Is the Rinda the only one? Im needing it to read 496ho 350mpi and 525 Efi. Does the tech mate read all 3 of these and just use different cable for 525? I’m familiar with the automotive scanners. Haven’t owned the marine version.

I bought one last year, told Rinda I wanted to scan Merc 600SCI, 496 HO and 300 Verado. They put together the correct adapter and 1 adapter fits all listed and that adapter will work with 525 also. Call them direct.
TechMate Pro marine diagnostic tool, marine code reader

Lots of threads here about the different scan tools available here. I use Rinda's Diacom Software. I've used it on 496HO, 525efi, Verados, and Optimax OB's. The Opti used a different adapter than the others.

I'm waiting to hear input on this as it's much less expensive.

OBD Diagnostics