I am not a fan of Pinot Grigio at all. In fact, it is the antithesis of my favorite wines, but to each his own (I like my wines "bitey"). Therefore, I do not have a favorite Pinot Grigio, however, I have found that the Santa Margherita brand is completely over-rated and over-priced. I have noticed that it is currently being heavily pushed by local super markets and can be found on sale at Dominicks and Jewel, but even at the sale price, I think there are Pinot Grigios that are much better for a lower price.
The "biteyness" that you find objectionable in Chardonnays, is likey caused by the oak barrels in which the wine is aged. Instead, you might try an un-oaked Chablis, which uses the same Chardonnay grapes, but is not aged in oak, so the wine does not have the bite produced by the tannic acid found in the oak barrels. If you like lighter, white wines you might also try a Grüner Veltliner or even a Viognier for an easily drinkable white wine with a little more dimension to the flavor.
At any rate, I was recently faced with a situation where I was specifically asked to purchase a Pinot Grigio for a friend. I asked one of the wine consultants at the Binny's in Niles (on Milwaukee) for some help and was directed to some excellent examples of the variety at sub $15 prices. Unfortunately, I do not recall the specifics of the bottles. If I see them, however, I will likely recognize them. I will keep an eye out for you. If you live near that Binney's you might give it a try. The store seemed well stocked with the variatel and the employee, with whom I spoke, was quite knowledgeable about the available choices.