Here's what I've been drinking from Caffe d'Arte - quite a bit of their Capri (which is a Southern Italian espresso), their decaf espresso (probably drink more of this than anything else) and most recently I picked up their Parioli, their Central Italian blend.
One of the big things I've recently learned is that their original master roaster Mauro, who founded the company, recommended a brew temperature of between 190-197 degrees Fahrenheit. That's quite a bit lower than I've been used to. In general now I think I see a relationship between the degree of roast and the more optimum temperature range for pulling good shots. The lighter the roast the higher the temp (think Vivace) and the darker the roast the lower the temp. The shots of d'Arte I've pulled at 195 and lower are very smooth and amazingly nuanced.