Here's my experience, FWIW:
I used
www.freedieting.com. Their standard formula is based on the Mifflin-St.Jeor equation, which is supposed to be the most statistically accurate from what I've read. Certainly, it's one of the more conservative ones I've seen on the Internet.
However, I, too, did not believe I could eat as many calories as some sites were telling me. I started w/ 1400 per day and stuck to that from 6/2011 until Oct. 2011. I had not weighed myself at all at that time, but by Oct. I was satisfied with how I looked, so I switched to what I
thought would be maintenance calories for me---1700 per day. Well, I noticed after 2-3 weeks, the weight seemed to be just falling off me. Skirts that I had bought at the beginning of October were getting loose. I could hardly believe it. I increased my calories to 1800. I seemed to keep losing. So, I finally decided I needed to know my real weight to get a true sense of my maintenance calories. I weighed myself the week after Thanksgiving, found out that I was 5 lbs. under my initial goal weight, and decided to increase my calories yet again. I won't bore you with any more details, but suffice to say that I am now at 2100 and seem to be able to maintain [so far] on that amount (perhaps even a bit more).
So, the moral of the story is that everybody's body is different. Use those calculators as a general guideline, but you'll need to experiment.