Fish finders for kayaks

I've got the Cuda 350 /s and seems to work great the couple times i've taken it out.  Has built in GPS and can be found online for around $180. I was happy I spent the little extra for GPS.

Thanks to everyone for your advice.

I'm also look at gearing up my yak and found this 1
Eagle Cuda 350 S/Map soft pack. 

Does any one have recommendations  I like the idea of Moblie

The compact Cuda features a sunlight-viewable 240V x 160H 4" grayscale SuperTwist LCD display and 800 watts of fish-finding power down to 600 feet. It also has Hands-free ASP™ operation, Grayline®, Advanced Fish I.D.™ and FishTrack™. Take it on the ice or switch boats with ease. Designed with water-resistant 600-denier nylon, the pack has a durable plastic frame for protection and web carry handles. It comes with a solid suction-cup-mount 200 kHz transducer with a built-in temperature sensor and rechargeable 12-volt, 8-amp battery and charger. Manufacturer's full one-year warranty.   $249.00 Cabela's

most people say, no suction cup ducer as it can get hit by kelp, underwater grass, etc and potentially be knocked off.  shoot thru hull will lose some sensitivity but it is much easier to deal with.