John Bucci, co-owner of South Philadelphia sandwich mecca John's Roast Pork, says roast beef has never been a big part of his business, which has been around since his pop opened it in 1930.

And that makes sense, given that his roast pork has won all sorts of awards, and his provolone cheesesteak made it to the finals of Adam Richman's Best Sandwich in America.

But there are those who don't care for roast pork or thin-sliced and griddled steak, and instead prefer roasted, thin-sliced top round bathed in gravy.

Bucci, however, says he lost money on roast beef, which he bought premade. He seasoned it and made his own gravy.

Then recently, he bought a new oven and his world has changed. This is a win-win.

The Alto-Shaam results in less shrinkage (for the pork, which he does roast in house) and as such, boosts him a modest profit.

And the new roast beef - judging by the taste-testers I enlisted - is incredible. It's so moist, you really don't need the gravy.

Bucci, who is quite passionate about the fact that he beat leukemia, is discounting the new beef sandwiches through Saturday, Feb. 8, knocking a buck off the usual $8 (large) and $6 (small) and donating proceeds to BeTheMatchFoundation, which connects potential bone-marrow donors with patients in need - just as he was.

Last year, Bucci raised $17,000. See the page here.