The important thing is what hardware your friend has. If he has an A1200 for example, then he might do better trying to get an 030 accelerator for it, and adding some memory to that. That would give him a very useful machine, and very good for WHDLoad. The 040 is not nearly as compatible as the 030.
He could do a lot worse than keeping an eye out on Ebay for this kind of thing, or if he wants to buy new probably amigakit.com.