I think you're spot on that its a preference but it shouldn't be. Depending on a number of factors one is better than the other in different circumstances if you can accurately weigh the odds of a given situation.
1. Can you run out, can your opponent do this also? If the answer is no to either then how many balls can both of you consistently run?
2. Are you a fast starter, is your opponent a fast starter? This is a factor that is huge that needs to be calculated before making the choice of balls or GOTW when either giving or getting a spot.
3. Length of set in a race.
4. Is it a race to a defined # or are you playing ahead sets instead, this is big & depending on how you match up with a particular player skill wise & also in mental toughness & whether you or he are quick starters or grinders makes this choice one of the most important ones.
Most important of all in matching up is an individual's nature to be able to HONESTLY appraise his own skill & that of his opponent without letting ego get involved in the calculation. You have to be able to accurately & honestly appraise yours & your opponents abilities for what they are if you want to consistently book winners. Ego needs to be left out of the equation on your part but if you can manipulate your opponents ego during the process of matching up this one factor can be more important than all of the others mentioned above.
Matching up is like a recipe for a meal, there are a lot of ingredients & depending upon how you assemble the ingredients it either turns out great or disastrously. A man doesn't have to only know his limitations or strengths but also to be able to objectively assess his opponents also, it's a delicate dance.
I remember when people used to equate the games on the wire to ball spots and it always made me question it. Like last 2 equals a game on the wire to 11 or the 8 ball is like a game on the wire to 9 etc.
I think the sets play totally different.