My sons went to a R-E preschool when they were three. They had a wonderful experience with it, but I suspect that as with any method of teaching a lot depends on the teachers themselves.
The preschool we stumbled on was a parent-participation / cooperative program where each parent was required to spend a day in the classroom every 3 or 4 weeks, which was a great experience. The mornings were structured and predictable, but in a way that the children were able to choose their activities. The weekly themes were chosen by the teachers based on not only season, but also what the children seemed to be interested in.
Their days looked like this: After starting circle time, the centres were opened to the kids. The arts centres such as painting and drawing were always among the choices, as were the housekeeping corner and train stuff. The craft tables changed according to the theme, and while the children were encouraged to do the daily craft at some point before snack, they were not required to do it. My sons were not the only kids who loved 24-100 piece jigsaw puzzles, so big floor puzzles were often brought out for them to work on cooperatively. They would go to a brief circle time after clean up and while snack was being prepared.
Then the kids would have structured snack time where they were encouraged to find their own place mats (name recognition) and pour their own drinks and things like that.
The third part of their day was always gross-motor play.
I couldn't have hoped for a better more well-suited program. Now, part of that had to do with the teacher, who was awesome. She did things like bring a copy of Stephanie Tolan's "Is it a Cheetah" article to the first parent-teacher meeting as something she thought might be interesting for me to read.
That was our experience. I hope it helps.
