In theory I agree you get more logical spacing with a triple than a compact double. But when I think about it, I haven't had a bike with a triple, barring passing encounters, in at least five years. And I don't find I miss them. Plus, what [MENTION=81059]NormanF[/MENTION] said. In these days of 10 and 11-speed drivetrains that can handle cassette cogs in excess of 34 teeth, there's much less need for triples.

That said, I don't have a 50-34 compact on any bike. My primary commuter has a 46-36 cross double, my cross racer has a 46-38 double (smallest ring I could get on a 130 BCD crank), and my road bike has a 53-39 standard double. With a 28T cog on the road bike and a 30T on the cross racer, they're as low as I ever need on my commute for sure, and in most other situations as well. The commuter is still quite new to me and I haven't changed out the cassette from the stock 12-25. That's adequate for me, albeit a bit stiff when I want to take it easy on the steepest slopes on my commute, but I wouldn't blame most people for wanting something a little lower.