Just another data point.

I am 64, and just went from 50/40/30 to 50/34 through no fault of my own. Well, I OKed the deal to get my new bike quicker, and as long as it works out, I also got more for my money in the bargain with the carbon compact: http://perso.wanadoo.fr/masong4/casati.htm

I am in the foothills of the French Alps, and was worried about losing what amounted to about 2+ gears with the new setup. I decided that I would just suck it up, and have not had any problems. The only time I ever used the lowest set of gears anyway was on climbs like le Mont Ventoux, so a little extra from my body will make up the difference. Good incentive to improve strength too.

On the plus side, it is a simpler setup, better axle/crank arrangement (ISIS), and fewer things to worry about when riding.