Weirdly the fastest tomato I know of after the truely tiny Gartenpearle is Black Krim.... a purple beefsteak with the most appalling growth manners you will ever find... but it is both early adn delicious so I forgive it the bi and trifurcating growth points, growing blind into leaves and trusses, throwing growth points off the end of leaves adn trusses and generally being a random mess in terms of a plant....