Common old Basic Ultegra works well enough and from what I can see on the TDF- Electronic gear changing seems to be causing problems.

I was beginning to struggle on some of our local hills using 50/34 and a 12/27 cassette. Got the Tiagra 12/30 and have that extra gear now that I rarely use but when I need it- I am thankful it is there.

And as you have found out- bikes and components have progressed in the last 5 years. Should give you a few more years before you need N+1 to stay with the fast boys in your local club.