I am offering my experience with scanning chips. Your response with opinions and experience are welcome.

At present I don't have a scanner. I sold my 10 year old Microtek ScanMaker 4800 because of a recent move. It used ScanWizard 5 software. 10 years ago I bought it to scan my collectibles and not for chips in particular. I was lucky because it was a CCD type scanner, the only type on the market at the time.

Basically there are two types of scanners. The older type is CCD and the newer type is CIS.

CCD - Charged-Coupled Device
Pros:
Great for scanning chips because of it's close to true colors

Cons:
Costs to build are higher than CIS type because:
It requires a housing unit
Uses mirrors and lens to focus the image
Uses fluorescent lighting

CIS - Contact Image Device
Pros:
Eliminates the housing unit
Uses LED lighting
Runs on battery power or powered USB
Great for scanning text
Built thin
Cheap to build, found in most All-In-One Printer/FAX/Copier/Scan

Cons:
On most occasions it will not scan correct chip colors
Will not clearly focus on objects not in contact with the scanner glass bed

Recently I bought a HP All-In-One knowing it had a CIS type scanner. I didn't buy it for the scanner; I bought it because it is a cheap running printer/copier. There are only two ink cartridges, black and tri-color. Both re-fills are $10 each.

I have scanned chips with the HP and compared them to the Microtek scans that are in my database. The scans are of the exact same chips and these are the results:

When a penny is pressed in an elongated coin machine it usually ends up curved. Only the middle portion of the coin is in contact with the scanner glass and the top and bottom portion of the coin ends up out of focus with the CIS type scanner. With a CCD type scanner the entire scan comes out clearly focused:

Conclusion: If you're scanning chips buy a CCD type scanner to get the close to true color. Also, some of the newer CCD scanners use LED lights and the costs have really dropped. Check the "Specifications" of a particular model to see if it is a CCD or CIS type.
(Currently it is Saturday, November 26, 2011 5:09 PM where I am)