So now I'm even more confused. I have gone to 3 bike stores. I'm between sizes and don't know who to trust.

The first shop measured my current bike which is a mens 48 (Giant small) and then put me on the trainer on a Specialized dolce womens 54. He said I was a specialized WSD 54.

The second shop I went to measured ME, and on the Felt, said I was a size TALL.

The third shop seemed the most knowledgeable, and he also put me on the trainer. He said I was a Felt Medium, not Tall like the second shop said. He said that I was a specialized wsd 51, not 54 like the first shop. He seemed to know the most but I'm just really confused.

According to the specialized and felt sizes, I'm right in between. I'm about 5'5'' or 5'6'' and that puts me in the in between range. Whats better, to be a little too big or a little too small?