If you want Spice of Life sweettooth #3 go with the Deluxe F2. Breeder Steve back crossed to the SPG mother quite a few times in the later versions which contributed to the problem one gets when sweettooth gets root bound and auto flowers.
Chimera's Grapefruit x Blueberry is a whole different ball game. The blueberry fathers were some stunning reversed blueberry mothers and the legendary B130 male which is now extinct. So the SPG had several different pollen donors and is F1 in nature (depending on whether the SPG cut was stable). I much prefer this hybrid. One of my all time favourites! Soon these will be gone as production has ceased.
The only problem with both of these varieties is that keeping mothers is a real pain in the ass as they tend to autoflower when the roots touch the sides of the pot. Also, both can be very susceptible to mould so watch the humidity levels.
The Survival of the Fittest Seeds Sweettooth #4 IBL got good reviews but I haven't tried it (although I have a pack). Dont think these are available anymore.