No it won't be the same as a plant grown from cuttings. I don't know your chances of getting good fruit. But I'd bet you'll not have to wait long to find out. It should bear fruit as soon as it gets some size. No fruit is more precocious than blueberry.

The seller assures me that the seeds are Sunshine Blue variety, but how can it be?
I guess you just can't be sure that the plant will be of the same variety of the mother plant because, if it is a seed, then it has DNA from the mother plant and ALSO from the pollinator plant, right? I mean, assuming that cross-pollination occurred and we don't know which traits where transmitted to the seed, then the new plant is a new variety that might have nothing to do with the mother plant. It may inherit the best features of the parent plants, or maybe only the worst traits... I know that some blueberry plants are self-pollinating but, you just can't tell if the seed you are buying was self-pollinated or cross-pollinated... So do you guys thinkg that the chances of getting a bad plant from a seed could be high? What are your thoughts on this?

A lot (most) of Blueberry cultivars are a combination of different varieties and types.Sunshine Blue is one of those,as are all Southern Highbush.
I think sometimes they take a native southern growing plant like,Vaccinium Darrowii(Darrow's Blueberry) and crossbreed it with Northern Highbush,sometimes multiple times.So it's really a hybrid.
That's why the seed won't be exactly like the Sunshine Blue plant it came from.
I only know of a few Northern Highbush,like Rubel that are the same like when they were found in the wild. Brady

I say go for it. This may be your only legal option. Plant several and select the ones you like. They root easily so you can propagate your very own variety from the choice seedlings. These seedling most likely wont be like the parents but what the heck, give it a try.

Why not use cuttings? Then you can guarantee the same plant as the cutting donor. Faster than seeds as well.

According to Mark K. Ehlenfeldt, U.S. Department of Agriculture researcher and blueberry breeder, plants from seeds of self pollinated bbs generally do not grow as well as those which are the result of a cross. I had asked him about emasculating flowers to control crosses, and he indicated such was not necessary as it would generally be evident which seeds resulted from self pollinization. This was in response to an inquiry regarding cara's choice. Perhaps other cultivars perform differently. But I suspect that if you get seeds, if they are true sunshine blues, they will not grow well, and if they do end up growing well, they are cross pollinated and are not sunshine blues.

There are no bad blueberries. You should just plant the seeds, in a spot where you can maintain the shrubs, and see what happens. It will take you 5 years or so before there is fruit to taste. When that happens, you can take cuttings from the plants that you consider to be superior, and those cuttings will be ready to plant in the ground in two years. According to my math, it will be 10 years from now when you begin to get significant fruit production from your blueberry patch. I think that blueberries are worth the time and effort, so I hope you are able to undertake this project. I hope that I am still around to hear of the results.

The seller assures me that the seeds are Sunshine Blue variety, but how can it be?

==>>> genetics rule ... the child will NEVER be exactly like momma or daddy ...

so.. it should be apparent why... the seedlings will not be either of the parents ...

and i doubt your seller knows who daddy is.. since the seed came from mamma ... [open pollinated versus some hopeful cross to improve the berry]

the result could be a better plant.. but the odds are.. it will be an inferior plant ... a regression of the gene pool .. from the extra-ordinary sunshine blue ...

ken

Yes,there is no harm in trying to grow the seeds out.But what was mentioned above by beeman gardener is the only sure way to get true Sunshine Blue plants and they are not patented to the best of my knowledge.
Propagation by cuttings is not real difficult.It helps to have a way to keep the leaves moist while the roots grow.
They can also be cloned aeroponically,but I haven't tried that yet.
Here is something I do. Brady

Here is a link that might be useful: Propagation of Blueberry Cuttings Using Fog

Thank you guys for all the answers, but I just can't use cuttings because this variety can't be found in Brazil and the international mail does not ship live plants, it's forbidden, so the only legal way for me to do this is from seeds :(

Unless you guys come to the FIFA World Cup and bring me some cuttings :-)