I actually did a recent experiment with this. I brewed 2 6 gallon batches of Dead Ringer IPA (with some minor personal changes). Identical grain bills, etc.
Batch 1 = 150 degree mash
Batch 2 = 155 degree mash
I also split both batches in half, fermenting 3gallons of each with 1056 and 3 gallons of each with 1272.
So, I ended up with 3 gallons of four slightly different beers:
150 mash/1056 yeast
150 mash/1272 yeast
155 mash/1056 yeast
155 mash/1272 yeast
Both had same starting gravity of 1.055
There was no difference in Finishing gravity between the 1056 and 1272 yeasts. within the same mash temp. However, there was a small difference in finishing gravity between the 150 and 155 mash temps.
1.014/15ish in the 155 batch
1.012ish in the 150 batch
Not a huge difference, but noticeable.
i have not compared them yet for taste etc. as I just bottled them about 2 weeks ago. Maybe try a couple of them later today and see how they are doing.