This is a great topic!
The short answer is ABSOLUTELY, yeast has a great impact on the wine, each yeast brings out specific characteristics of the varietal that you are making.
To give you an example:
In 2014 I purchased enough Cabernet Sauvignon grapes to make 35 gallons of wine, after crushing and destemming I split the Cabernet into 2 batches and fermented one batch with a traditional Bordeaux yeast - BDX, the other batch I fermented with RP15.
Both yeast came highly recommended by Scott Labs, not to mention the positive reviews given by fellow winemakers.
I chose BDX because it produces a traditional Cabernet and it brings out berries, plum, and jam flavors in the Classic Bordeaux style, it increases mouthfeel, and brings out the tannins.
This wine is everything that I wanted in a traditional Cabernet Sauvignon.
I chose RP15 because it makes a rich, concentrated red wine with a lush and balanced mouthfeel.
RP15 brings out the varietal and red fruit character, it brings out the berry characteristics creating a fruit forward wine, with color stability, and mellow tannins.
This wine is a crowd pleaser, it has a really smooth mouthfeel, almost silky, the berries are balanced, they do not over power the other characteristics.
I highly recommend the Scott Labs Fermentation Handbook
- Click Here -
It is an invaluable resource!
I hope that this helps.