R.R.
I used the potty chair for all three and would do it again, it seemed to make them more secure than climbing up to sit on the toilet and less frightening. My older kids had a wood potty, with built in toilet paper holder on the side and loved it, for my little guy I used the Fisher-Price Froggy Potty and we both loved it, too. It kept him low to the ground and secure, has a high front to prevent spillovers with a boy, and no splash guard to get injured on, the pot was easy to clean, I see it now comes in pink for girls.
http://www.walmart.com/ip/Fisher-Price-Froggy-Potty-Train...
But one of my grandsons learned strictly on the seat on the toilet, Mom said she didn't want to have to train him a second time so it was as simple as to stop using the seat when he was big enough.