I waited until all my kids were two and a half to even start potty training them. I didn't get any trained until they were almost three. My youngest daughter wasn't trained until just past her third birthday.
None of them are wearing diapers now.
You have to be aware. PT is an area where parents become know it alls. If something works for their child, then they assume that every child has to be trained when and how theirs were. They also compete with and judge one another based on whose child was trained first. It is very silly.
When you do potty train your son, don't make him sit on the pot until he goes. Just sit him on the chair while you use the bathroom. Let him up when he wants up. So, he sit there for a second. That is an accomplishment.
I would wait until summer to potty train anyone. That way you can let your child run around without his diapers. It is very easy to tell when a boy needs to pee. So you can set him on the pot right away.
With my boys, I let them go into the bathroom with their dad. After he was done, he would tell the boys that they could copy what he just did. Our sons got so excited to stand at the big toilet(on a thick book) and try to copy their father's stance. It didn't matter if they actually peed, the ritual got them excited about being potty trained. It was also very cute.
I don't think that my sons ever peed in the potty chair. They went straight to using the big toilet.