I would say it depends how close together they're planted and how much direct sun they get.

For instance, if the row runs east-west and there's nothing tall planted to the south, I'd be happier about leaving them as they are.

But if you've got a block of plants 2-3' apart and there's a determinate with indeterminates to the south and west of it, that's another matter.

well my row of planter runs North south and I get full sun from sunrise to sunset. the row is actually perpendicular to sun's patch so my North South row is good I guess. I get yor point. I plante then 20 to 24" apart. I know its a bit too close but I did well last year and I wante to get few varities this season. Good thing is if I got it mixed, I got at least 2 or 3 of a kind next to each other so that would help somewhat from overtaking issue

thanks for replying

Every year I plan to put indeterminate tomatoes with other indeterminates, and the determinates all together and every year I wind up not doing it. I plant my tomatoes three feet apart and have run them in north-south rows and in east-west rows with six feet between rows and have never seen a problem that I could say was due to mining indeterminate and determinate tomatoes.

I suppose with closer plantings, it could be a problem, but I think if your garden has full sun, it won't make a difference.

Betsy