Sun Gold Tomatoes F1?

Not being a Tomato expert should to be born in mind when reading this!, however, I have been growing Tomatoes on and off (off when not enough time or greenhouse) for a fair few years.
I grew Sun Gold last year and was very pleased with the results so sourced a large supply of seeds (a la @Scrungee giving a great tip about a seed offer) which should last me for about 5 years.
When I was planting up my greenhouse this season with the Tomatoes I started in a heated propagator I noticed a couple of self seeded Tomatoes growing the the soil borders of my unheated greenhouse. They were sort of in the way so I lifted them and planted them in pots but still in the greenhouse. I was pretty certain they were self seeded from the previous year's Sun Gold. As they are purported to be F1 I didn't know what I would get from the self seeded ones but thought I'd just see out of interest.
Well they grow in a very similar manner ( plants not growing as big but they are restricted unlike the border grown ones which would be about 10 ft by now if I hadn't stopped them)..The trusses look identical AND I have just eaten 1 of the 1st ripe 1s. The fruit is pretty well the same size and orange and taste incredibly similar if not identical!
If I live long enough to use the supply of bought seed I think I will just save seed and grow from that as I already do with Garden Pearl with good results.
Would it be the case tho that after maybe a couple of years of using saved seed, that eventually I would "breed" away from the same traits as Sun Gold? Maybe they aren't F1 and are just advertised as such to keep us buying it rather than saving our own.

 

@silu

For many years I would sow just 1 packet of F1 Sungold seeds, normally bought for 25p or so when I found them at car boot sales, and would also sow many dozens of seeds saved each year or so from the tomatoes grown on those F1 plants.

When a lot of F2 Sungolds are grown out, the variations in size and colour become noticeable, but all the F2 tomatoes have been just as sweet and tasty as F1 fruit, and as the majority of them were turned into roasted tomato pasta sauce the only noticeable difference was the huge saving on seed costs.

There is an ongoing project on a U.S. tomato forum to produce a stable non-F1 Sungold. Giant tomato growers have now produced stable non-F1 Big Zac tomatoes that are now producing bigger fruits (like the World Record) than the original F1s.

Another relatively expensive tomato, Red Alert (a very early bush tomato) will produce seeds that will grow F2 plant virtually identical to F1 Red Alerts, so I also save seeds from these each year just in case I can't source dirt cheap F1 seeds.

 

Very interesting @Scrungee. Thank you for the information. I am lucky as I get most of my seeds for nothing as husband knows someone responsible for filling/emptying seed stands at supermarkets/garden centres etc. He gives away 100s and 100s of packets of seed at the end of each season. Some of more use than others! I think I have just been brought home about 10 packets of Oregano and Cress seeds, anybody like them. Husband is NOT a gardeners and it shows
By not having to pay what can be a fair few bob for seed, it softens the blow if you get zero gemination!
I don't quite understand why in this day and age of the "new" idea of recycling, why more people don't save seed when it's viable to do so. I already do for Garden Pearl Tomatoes ordinary Peas and Sugar Snap Peas, it REALLY isn't difficult. Sure some seeds must be tricky to collect but from my limited experience some are not. Scrungee, husband is bringing back a huge box of god knows all what seeds next week, is there anything you might be wanting? Most (not all ) are Unwins. Happy to send you anything which might be of use in return for your great alerts re bargains. You have saved me loads of money with your "finds". I currently am enjoying the lovely Galtonia flowers C/O a boo boo by Van Meuwen you alerted us to whereby I got 20 bulbs for not a lot!

 

@silu Genuine F1 Sungold leaves have a distinctive smell, that's a way to check if 'Sungold' tomatoes at car boot sales are from F1 or saved seeds.

 

I'm all for experimenting with growing stuff from your own seeds, but cost? I got my tomato seeds for next year(all Suttons) from the Dobbies end of season half price sale for around a pound a packet. Takes away the risk of expending a whole growing season and ending up with an inferior crop, ditto using cheap growbags, can't see the point in them really.