Pondering a Fisheye Adapter

[f50fan]

Okay, so here it is.

[ame]http://www.amazon.com/exec/obidos/tg/detail/-/B0007RRGBM/ref=ord_cart_shr/104-7148324-1768705?%5Fencoding=UTF8&m=A1P9QRDRYY6FXL&v=glance[/ame]

It's $80. XP. I really like the fisheye effect and know i wont be getting enough money for a real fisheye lens ANY time soon. (high school student with no job) So my question is. Is the quality loss really that bad that i shouldnt get it? Also. For you who have dealt with these. the lower the .22x or whatever number means its fishier right? So yeah. Give me your advice on this. Please? Thanks tons!