What do you mean by yield - weight per plant, per limited space or most per harvest.
I have never grown any, but for biggest yields per plant, among autoflowers I'd presume the superautos win out, such as those from Flash Seeds. But with these plants being bigger and taking longer, superautos might not be the most efficient use of limited/indoor space and a faster-finishing strain might ultimately be more productive. But superautos may be what you're looking for.
Otherwise, high yielding plants, even monster plants, may not be the overall highest yielders in terms of overall harvest where space is limited (indoors). For example, jamming a lot more plants in and doing SCROG or other intensive training might get more weight per indoor growing area (ounces/sq. ft.). Something else to consider.
Just getting my average ≥3 oz per mid-sized plant jammed in a tent, I average about 2 oz./sq. foot. When I look at many of the larger monster plants, even if they provide double the weight per plant, it looks to me (doing the math) that they are not hitting 2 oz/sq. ft. For example, a 2.5 x 2.5 foot plant takes up 6.25 sq. ft., and needs to yield 12.5 oz. to meet 2 oz./sq. ft. The loss of yield/growing space becomes bigger with bigger plants.
