I don't take cabs often but I tend to call Checker when I do. The women who tend to work the call centre are usually pleasant. Last time I used them it was late evening and I only had to wait 10 minutes. I've found even into the wee hours of the night they always have adequate cabs available. The drivers vary in their friendliness. A lot of the cabs have interac and they all take credit cards. Also the cleanliness of the cabs can vary, usually they are pretty clean.
Checker is a good choice for your taxi transportation needs.