fishfinder gps combos ?

[markb]

I considering purchasing a gps fishfinder combo the humminbird 161, $299 local walmart. It seems these units would save space in my new hobie quest and require only 1 battery. I plan on fishing the central cal coast. I have used fishfinders before but have never used a gps. I know this will limit the gps to my boat, unlike a handheld which used anywhere but i dont know I have another need for a seperate gps. would appreciate any input pros or cons ?