Not all TI is expensive, with Habanero you can a quality ti frame for as low as $895, or a completed bike with either Shimano 105 for as low as $2,281 or Campy Veloce for as low as $2,012 not including pedals. Or if you want bargain basement TI, Motobecane LeChamp fully equipped with Ultegra is only $1699 including pedals at BikesDirect.

As far as reliability goes...ah who cares these days with al and cf bikes all designed for the short term anyways...just kidding...I think? anywhew a good quality ti frame should last longer then either AL or CF, poor quality and those uber lightweight TI bikes could be another story because to get that weight down the tubes are thinner and some of these have been known to tear. As far as being stronger then steel...only time will tell since none have been around for more then 30 years not alone over 100 years as some steel bikes have lasted. But I will tell you this, I'll take a cromoly steel sword over a TI sword any day; and structurally in aircraft steel is superior to TI; so to make a blind statement that ti is superior to steel is just pure ignorance.

http://swordforum.com/metallurgy/titanium.html