1st play through – with custom 6 party – will I gain xp fast enough to max out before the end?

I chose to build a custom party from the get go because I had no idea how several classes would play for a main protagonist, and wanted to try them out all at once to get an idea what appealed to me more. I'm wondering is my xp getting split 6 ways, or is it the same across the board? I played this 1 time when it first came out forever ago, and don't remember how xp works in large party's. If it matters, I'm playing with a kensai, dragon disciple, cleric, assassin, illusionist, and archer.