Which Groupset?

I ride all the time with 105 - wouldn't call it commuter since It's my weekend bike too - I don't want to go higher as it will wear faster for little gains.
Ride whatever you can afford to replace when it's worn out, as you go higher things cost more to replace and could wear out faster.

No one said Ultegra wears out faster. I find it exceptionally durable.
I do use cheaper chains and cassettes on the winter bike.