Thank you for the suggestions regarding Marie's pie sale. I ended up trying "Double Cream Lemon". The crust is pretty much the same as the Marie Callenders and Mrs Smiths frozen piecrust available in supermarkets. The filling has a nice tart lemon layer on the bottom, but only about 1/2 inch deep. On top of this was a 3/4 inch layer of light sour-cream-lemon. This top layer doesn't have much flavor except for a hint of sour cream taste. And piped around the pie is a very light and airy version of real whipped cream.
I would rate this pie about a 5 out of 10, but the bottom lemon layer tasted quite promising so I think I might try just regular lemon meringue next.
P.S. When I asked the girl what their most popular pie is, she said "Banana Split Pie but we don't carry it anymore." That doesn't make too much sense now does it?