If you're looking for a high-end tamper, the Ergo Packer is a great choice!
Positive Product Points
The Ergo Packer is extremely solid (not easily chipped like a wooden one), allows one to screw on different sized pistons, and has several lines on the tamper, which ensures that one can pack the grind evenly in the coffee basket.
Negative Product Points
It is not inexpensive.
One might be quick to dismiss the difference a tamper can make, but the plastic tamper that arrived with my Pasquini Livia 90 was completely inadequate, and an upgrade was necessary in my opinion. In order to apply the required amount of force (at least 30 lbs. force), I needed something more solid. Also, the plastic tamper did not properly fit my coffee basket.
Thus I ordered the Ergo Packer with a 58mm piston to fit my Livia's portafilter. The first thing one notices is the tamper's design, with its all turned-Aluminum look - quite professional! On the top of the piston it reads "58 ERGO-PACKER 58 VIVACE." The screw-on, screw-off piston allows one to have multiple piston sizes (available from Espresso Vivace for $15 each) and just one handle. The tamper feels great in my hand, and is quite comfortable. It has a very slight convex shape to the tamper's bottom - a change that David Schomer made from the original Ergo Packer's, which had a flat bottom. The tamper has a nice weight to it, and made a noticeable improvement in my shots (compared to the cheapo plastic tamper).
I purchased my Ergo Packer tamper online from Espresso Vivace, which uses these same tampers in their cafes in Seattle. The transaction was a smooth one, and the tamper arrived in the mail shortly after my order.