Originally Posted by
icemilkcoffee
Reliability is very good with modern STI, but they do tend to gum up with high mileage. Especially in cold weather.
Whereas downtube shifters are much more foolproof. There is little mechanism to gum up, and very little cable housing to wear out. Another advantage of DT shifting is the mechanical feel. You can really feel the gear teeth engaging with the chain.
Downtube indexed shifting is the best option option for people who want to try out DT shifting. As for friction shifting - I see no reason for that to exist anymore.
I never had these issues, even on my mountain bikes. So reliability for me is a moot point. My current main road bike doesn't even have any cables.
There are currently no advantages in DT shifting that would even remotely interest me. I'm old enough to have gone through all the developments in gear shifting from friction DT 5-speed onward. At no point along that 50 year journey have I ever wished to return to DT shifters or friction shifting.