tranzformer wrote:it seems like some think DA lasts longer and others argue Ultegra lasts longer.
It probably depends on the failure mode.
I've found for sheer durability, shift after shift after shift, the "working" bits of D-A just last. Forever. (Brakes, shifters, Fr/Rr mechs, Hubs) 4 or 5 seasons is doable, given a lack of crashes and extreme weather. Ultegra will do a couple before it gets sloppy and too annoying to race on.
Soon as you start adding in the consumables, Ultegra begins to look more sensible. (Cassettes mainly, as D-A chainrings last rather well compared to Ultegra). 2 ultegra cassettes a season, 3 D-A, maybe 4. (only used two D-A cassettes, ever. Bought at the same time on a deal, both worn out before the season was over. Stuck with ultegra after that)
Once you stick a bit of salty corrosive sweat and road salt/grime, rain and so on into the mix, i found that the D-A started to deteriorate much faster. Maybe this is as it's more refined and susceptible to the degradation, or maybe its cos the odd missed shift on a manky Ultegra groupset is acceptable, as opposed to a manky D-A groupset........ on my training bike, D-A shifters only lasted 16-18 months before i got fed up with missed shifts, then they got binned, the Ultegras that replaced them are still in use, 7 years later.
This is all on older stuff, but i suspect the same still applies. Roughly.