Welcome to Coffee Snobs.
The 0480 had a metal body and a 3 position power switch; On/Off/Auto
The Auto position works with a switch on the front of the body under the coffee exit spout that is activated when you push the portafilter handle against it.
It may also have a slightly better warranty. Not 100% sure on that.
In my opinion either of those two are the absolute minimum grinder you would buy.
I have the 0450 and replaced it pretty quickly with a Gaggia MDF.
The Sunbeams are noisy and messy and prone to grind consistancy problems.
They also retain a lot of grounds in the grinding chamber which will go stale and affect the next coffee if you arent very particular with your cleaning.
Providing you buy one with your eyes open theyre OK.
If you buy the next best grinder it will be cleaner, quieter, probably last longer and save you $150-200 you wont have spent on the Sunbeam.
What machine will you be pairing it with?