Buschur Downpipe

I was going to get the Buschur racing race downpipe moslty becasue my cat doesnt have any flanges but i have 3 questions about it. One,I should be able to just cut it where i need to and weld it to my cat right? Two, will it bolt to my stock o2 housing? or will that need modifying as well. And three, does anyone know where i can get it for cheaper than 300$ the only shop i found selling them is machV and it was still 300.
pic http://us.st11.yimg.com/us.st.yimg.com/I/machv_1930_117316122

Not to thread jack or anything, but since it's along the lines of downpipes, is there a huge difference between downpipes such as this one, and the ones you see on ebay for ungodly amounts less it seems? Is basically limited to metal quality and welds?