Originally Posted by
vascof1
Appreciate the insights. My back is ok at the moment. I know does a great job with their isospeed.
If your back is OK, then why do you think you want an endurance frame? I'm not saying you shouldn't, but if you are young enough and flexible enough, you might find the race geometry more exciting. I'm not young, but some years ago when i was shopping for my first high end road bike, I thought I should get an endurance frame because that's the kind of rider I thought I was going to be in late middle age (though admittedly, I had already been riding a race frame for a while). I test rode Roubaixs and Felt Z series, but then also test rode a race frame bike. The endurance frames were, to me, boring and flat in comparison. That's when I bought the Felt F3 and I've never loved a bike more.
In other words, maybe you should test ride a race framed bike? Who knows what you'll think.
They are not just for racing and if they fit you right and if you have the flexibility and fitness, they are perfectly comfortable for centuries and more.
Either way, for an introduction to modern road bikes, I think an alloy framed 105 bike is the perfect place to start. If you get a lot more serious, you'll buy a better bike soon, but you'll still appreciate having the alloy/105 bike in your stable. Mine is 10 years old with >30k miles on it and I still get use out of it.