Similar experience with Torquecal
I'm running the FSA 50-34 up front and an aluminum 12-27 in the back. On yesterday's training ride with a bunch of guys who will be riding solo in the 24hrs of the Old Pueblo next weekend, we put in 65 miles, including a major climb at the far point of the out and back. When it got steep, everyone else was out of the saddle groaning and straining to push their 39x25 and 39x23 combos. I spun right on by in the saddle using the 34x27 wearing a smile. In the flats, it made no difference.
However, on the part of the return trip after it was no longer too steep to pedal, but not flat, I got burned by the guys who had 53x12's and 53x11's to push. I couldn't keep up. So, what's the answer? It depends! On balance, we probably were equal during yesterday's ride; I had a climbing advantage and they had a descending advantage, but my advantage only kicked in when it got real steep. It is more likely you (and I) will encounter more long gentle descents where we are disadvantaged. Eventually, as I get stronger climbing, and can switch to a smaller cassette with an 11 tooth small cog, I will close that gap. I wish I could find an 11-25, but no one seems to make that combo.