Ok there are several things.

Let me explain.

If you want a cheaper alternative go to http://www.google.com

And search for the powerbook guy.

It is a shop based out of california and they sell drive adapters and recycled ibook powerbook macbook stuff cheap.

The issues of the drive not fitting have to do with this original issue.

When apple releases two versions of the same laptop they usually change the drive connector or battery.

A great example of this i own a powerbook g3 pismo i found out there are two zip 100 drives for the pismo.

One fits version 1 powerbook pismos.

the second fits the powerbook lumbard edition.

The difference is the drive plug only.