The Back Bowls and Blue Sky Basin are what Vail is all about IMO, though there are plenty of good runs on the front too (Chair 11 = Northwoods area, Game Creek Bowl on the opposite side can be good also).
I'm guessing that the lady friend told you BC was more boarder friendly probably because Vail has a lot of cat walks to get to other areas... For example, to get from the front of Vail to Blue Sky Basin... normally takes like 30min at least. But its not too big of a deal.
Beaver Creek is awesome - probably my 2nd favorite of the Epic resorts out here, after Vail. Steep, a lot of vertical (over 4k I believe). Royal Elk Glades are awesome if there is good snow. There wasn't enough snow last year to go, but Stone Creek Chutes are supposed to be pretty cool too (pillows/cliffs).
You'll have fun at either place. One other bonus of Beaver Creek... at 3pm they bring out warm Chocolate Chip Cookies every single day.