I have a 1198c console mount. Looking to add something to the bow just wondering about what unit to add don't want to destroy my budget looming at the helix 5 maybe 7 but want something asap. Thought about trying to get a used 898 or possible 899. Should I get a si unit on bow too or look just at di with say a 859 or something

I use Side Imaging at the bow.

If you get a Helix model you cannot connect it to your 1198 to share data.

Yea I don't plan on connecting I don't think as that's another added expense