Fish finder recommendations?

Planning on upgrading my kayak here in the very near future. And I would like to get a much better quality fish finder than the one I have now (The Garmin Striker 4). I like the one I have now just fine however...

1) I would like it to be a little bigger
2) I would like to be able to zoom in on the GPS map a little bit more than I can now (in order to pinpoint exact locations on reefs) I think the Striker 4 can zoom in to a 20' area or so

Other than those 2 things (which I'm pretty sure I will get with any of the more expensive units) I am not sure what ones I should go for. I like how this Garmin I have has been one tough sob, taking waves through the surf, rolling into the sand. It seems fairly waterproof and keeps on going. I've messed around with a few more expensive Lowrance units (both on boats and in the store) and I like them, but at the same time I've heard very good things about Hummingbird units too. I just need a few testimonials about which ones people like using specifically on kayaks. Easiest company to deal with warranty wise if anyone has had any experiences with returns? I will mostly be fishing the ocean and I'd like to stay under around $500.

Let's hear it!

This is a commn topic if you look for it, but... I have a current model Humminbird 5" DSI GPS unit and I have two Lowrance units: a HOOK 5 (Version 1) and an Elite 4.

I'm not terribly impressed with the Humminbird because the menus are not terribly deep and the display isn't as customizable as the Lowrance units - bear in mind these are the older Lowrance units and I've never used the newest ones.  They've simplified the menus on the HOOK2 series.

I had a Lowrance Elite 5 that failed and Lowrance replaced it for free with the HOOK.  The exchange took 7 days from initial contact with Lorwance to a new finder in my hands.  Phone in Technical Support was great - well above average.  The Humminbird hasn't had a problem so I can't comment on their service.

For what it's worth, in my opinion, the Humminbird's 5" wide view screen appears considerably smaller than the more square screen on the HOOK 5 when I'm searching for something because the screen is shorter top-to-bottom.  I prefer the view I get on the HOOK unit, but that could be familiarity.  I just switched my primary kayak over to use the Humminbird this year so (fingers crossed) I'll become more used to it.

Another thing you might find important: the Garmin and Humminbird units allow you to make custom maps - Google it - within the unit.  Lowrance makes you upload the data to their web service and download them before they're usable.  I also fish smaller rivers that don't have navigational maps and that was the deciding factor for going with the Humminbird.

I'm giving one of the kids the Lowrance units if they ever come pick up the kayaks I've been keeping for them, leaving me one finder short.  I'll probably go with a Garmin Echomap as a replacement.

One thing to bear in mind - maybe it's just me - is I tend to stare at the 5" screens more than I stare at the 4" screen, and that's not very productive.  Your mileage may vary, but it's why I stick with smaller displays.

THE GRAIN OF SALT:  I fly fish.  Fish finders aren't as useful for me as they may be for you because every cast I make lands well outside the transducer cone, and I don't fish in water deep enough to compensate for that (it takes a long time for a fly to get down to 60' sinking at 10 inches per second and I'm rarely fishing in water more than 30-40-feet deep).  I'm looking for bottom structure and objects on structure more than for fish.  The Humminbird is noticeably better than the older Lowrance units for bottom detail.  The Garmin finders are noticeably better than the Humminbirds.

Good luck in your search.  A finder is a significant investment and which one to buy is always a tough decision.

All good info, thank you for replying! I have searched a little for peoples recommendations but definitely wanna do as much research and ask as many questions as I can. That is particularly helpful hearing a good experience with Lowrance's  customer service. That is a major consideration I have and tells a lot about the company when they are willing to stand behind a product.