Greetings from Sheraton Pleasanton. This is my second of three scheduled stays this month. Needless to say, I like this place. My reasons probably reflect my unique biases, so read them with due caution.
Location: Okay, it's in a mall parking lot. It's also directly adjacent to the BART (Bay Area rail system) station. Parking is ample for every visit I've had. And, worst case, park across at the mall. Maybe visiting between Thanksgiving and Christmas should be approached with trepidation.
Check-in: So far, it's been smooth. My keys are always waiting, and my amenity (points) is always offered without prompting. I should note that rates are often quite low here, especially on the weekend.
Room: I usually get a room NOT overlooking the freeway. I'll call that an "upgrade", in and of itself. Nothing terribly special about the rooms, though they have both wired and wireless internet access (free); both work. Good 'ol Sheraton beds.
Other facilities: I demand a good fitness center, and this meets my needs. 24 hours and never (during my stays) overcrowded. Like a previous poster, I notice an "off" smell, but only for the first thirty second of my visit. Maybe my nose is going numb.
Lounge: I agree that the design is odd. I've found the food offerings to look "a bit above average". Real oatmeal in the morning, along with a bunch of fruit, several varieties of bread, scrambled (?) eggs, decent coffee. (I'm vegetarian, so I've only actually tried the fruit and coffee.) Evenings, a hot dish and usually sandwiches and salad. Service can be friendly, but I've also had the hostesses retreat to the back room for the duration of my stay. I try not to take it personally. I should note that I'm usually here during low-occupancy period (read: "cheap"), so I've never seen any other guests in the lounge, period. Closed on weekends. (I don't know what substitute is offered.)
Competition: I've always really liked the Four Points, just a mile or so away, for it's really delightful grounds and great staff. At the Sheraton, I give up the trees and greenery and get a slightly nicer room, better gym, weekday lounge, Link area... For now, at least, the Sheraton is my preference.