While in Rome I did have the pleasure to attend weekday Mass in this church -- really more of a chapel. In point of fact, I was quite surprised by how small San Gregorio really is. This highlights again how much of a blessing the new situation with Ss. Trinita really is.
Here are some images from the last Sunday Mass:
(Unlike the new church, located on a small piazza, San Gregorio is located down this dead-end street and was very hard to find. In fact, because there is not really a facade per se, simply looking down the street, one would be hard pressed to notice there was a church there at all.)
For an additional treat, the same Spanish gentleman who took these pictures also recorded the entire Mass. Here is a clip from the beginning of that Mass:
