Originally Posted by
somebadlemonade
For the average joe, meaning non-racer it would have to be the 105. It seems to be the best of both worlds. And it also gives the option to start racing, if you really want to.
Your groupset has nothing to do with your racing ability.
You might drop a chain, dog fang will stop that from happening. I know someone who races an intro category with sora, she does fine and will move up.
Tiagra shifts fine and so does sora if dialed in.
I've kept up with guys on custom serottas while riding my 84 trek steel frame in crits. It's the engine.
Beyond 105, it's weight.