You are going to have to experiment and see which approach works best for you in your growing situation, Sumilea because other than the "never prune determinates" bit you will never get a definitive answer or agreement - as all the many past discussions and debates here on this issue will prove. ;)

The schools of thought on radical pruning vs. limited pruning vs. not pruning all have their diehard believers, their research, and their experiments to support their particular beliefs. All with equal validity because there are so many factors/variables involved - sun exposure, types of supports, air circulation, disease incidence, fertilization, size of container/garden bed, amount of time to work on the plants, soil composition, etc., etc. It is impossible for any to claim that this is the only way that works....tho some do try. ;)

My question is if you don't prune for increased yield how bad will the size of the tomatoes effected?

This claim that one needs to sacrifice one to get the other (yield vs. size) doesn't always hold true either so experiment and remember that size is predominately a matter of variety genetics. See if your pruned plants in your garden produce bigger or more fruit than the un-pruned ones do when all are subjected to the same growing conditions.

is it better to have 1 or 2 suckers grow or just leave it to 1 stem

Again, it depends on your growing situation and the form of supports you use. Try both and see which works best for you. That is how we all learned what works best for us. ;)

Dave

Sumilea,

You've just received an absolutely great answer from Dave. I can add nothing of value to it.

Psst....Dave; If you're not careful, you're gonna be flooded with folks seeking knowledgeable, unbiased advice. ~grin~ (just kidding...keep up the good work!)

Hal in PA - Z6