Not many Mad River kayaks around South Cal, not sure... Wilderness is better established brand. Try as many different ones as you can is the best advice you can get. Do your research:
http://www.fishingkayaks.net/subnav/...ion_guide.html
http://www.kayakfishingsupplies.com/...ayak-selection
http://www.kayakfishingsupplies.com/...k-buyers-guide
http://kayakfishingstuff.com/choosin...hing_kayak.asp
Curios - why sit inside? Sit-on-top seems more popular.