The aggreagte finishes (like PebbleTec) may last longer but also cost more. There are plaster finishes that have been around for 30+ years - with proper water care. I think if you get sloppy on the care, the aggregate finishes will be more tolerant. Regarding the darker finish, you can get aggregate finishes in whit if you want. I went with plaster because it was 25% cheaper than aggregate and I like the smoother finish.
Good Luck