The seeds will produce many vines. HOW LONG it will take for them to sprout is relative to the temps you provide - patience is the necessary virtue in growing from seed!

The issue is are they hybrids or heirlooms/open pollinated varieties. If they are hybrids then the seeds you save won't breed true. Hybrid seeds in the packet are the result of manual cross-pollination of at least 2 parent varieties. The seeds saved from those hybrid plants once grown, will revert to the parent stock or some strange combination of them. If your seeds planted and grown are heirlooms or open-pollinated plants, not hybrids, then yes you can save the seeds and re-grow them. Depending on what the plant is - self-fertile like tomatoes or insect pollinated like most flowers, they may or may not grow true. In some cases, like hollyhocks you will still get lots cross-pollination by insects so your saved seeds may change color etc. It all depends on how much you care whether or not the seeds you saved breed true or not. Many don't care, many do. Some research on cross-pollination will explain this in more detail. ;) Dave

If there is any difference between the two varieties, then it is likely hybrid, you just do not realize it. It is very hard to tell anyhow. I believe most of the vegetables, like toms, beans, peppers, and many many others are hybrids. The production is so high. Growers can't make $ if they grow the low yield heirlooms. With this, sometimes the difference is small, sometimes it is big.... To a lot of people, we probably do not even care. I still have many named variety seeds. But sweet pepper is just sweet pepper....

While it is really somewhat questionable to plant seeds from what are almost certainly hybrid tomatoes, since what you get may be a formally edible but unexciting fruit, it should be understood that planting seeds straight out of a plant is not optimal for germination. Mature seeds should be fermented, by placing them in water with some of the pulp and left in a warm place for a week. Then wash off the icky stuff and dry. Tomato seed harvesters know this strategy well. Here's why. When seeds mature, they are naturally encased in a protective gel coating. This is the slippery coating around seeds when they come out of the fruit. That gel coating has a hormone called abscisic acid that actually inhibits germination. That's why when you crack open a mature fruit, the seeds aren't all already sprouting! Microbial fermentation is an easy way to break down that gel, metabolize abscisic acid, and allow germination. Not all seeds have this protective gel. Solanacea and Cucumis commonly do. Some may say that, hey, I can plant mature seeds without fermentation, and they grow fine! That's because sitting moist in soil, especially anaerobically, the gel will break down naturally, But it will require more time, and may not work completely. That gel is natures way of making sure that new seeds don't sprout in the winter, but will wait a while, ideally until spring. FWIW, fermentation can also kill off disease spores.