I searched the web last winter on finders around the same price and narrowed it down to 3 units the lowrance DF 107,the Garmin 340C and the furuno FVC-620.All 3 are color finders all have over 300 watts of power for fishing deep and are dual frequencies but I believe you can buy models that are only 1 frequency(200 KHZ)the lowrance come with speed and temp so you don't have to buy them separately.I believe the Garmin does also.The Furuno you have to buy a tri ducer that has speed,temp,and dual frequency and a 2 year warranty.The lowrance had a higher pixels rating than the other 2 as far a screen is concerned.the lowrance and the Garmin are around $500.00 the Furuno is around $800.00 and is digital but you are able to hook your GPS up to it if you want.I went with the Furuno because I fish Lake Ontario and it was highly recomended by people who fish the Lake, also I needed the power for deep water.but I almost went with the DF107 I looked at it at the sportsman show last winter and it is a nice unit for the $$ but color is the only way to go you will love it.I just thought I would put my 2 cents in.

Erin

Myself I didn't use the temp/speed sensor that came with my Lowrance 337. I use the 337's GPS for speed and the regular ducer that comes with it has temperature allready.

John S.

I should have said "surface temp" in my last post.

John S.

John I agree the speed is alway way off on my finder compared to the GPS speed reading.I do use the temp reading for the spring time.I have a cannon temp probe for the summer as far as down speed and temp is concerned and is right on the $ with my GPS speed.

Erin

I did the same thing as John S -- i did not install the speed wheel with my 337c...fewer holes in the boat. I just use the GPS speed, which from most of the reports posted seems to be what most people are looking at for speed.