The invention provides a composition comprising a first composition, which first composition comprises the following: A) a first interpolymer comprising, in polymerized form, ethylene, an a-olefin and a nonconjugated polyene; B) a second interpolymer comprising, in polymerized form, ethylene, an a-olefin and a nonconjugated polyene; and wherein the first composition has an [(ML(1+4, 125 DEG C)) / Mw(conv)]*1000 greater than 0.429 mole / g. The invention also provides a composition comprising a first composition, which first composition comprises the following: A) a first interpolymer comprising, in polymerized form, ethylene, an a-olefin and a nonconjugated polyene; B) a second interpolymer comprising, in polymerized form, ethylene, an a-olefin and a nonconjugated polyene; and wherein the first composition has a Mooney Viscosity (ML, 1+4, 125 DEG C) greater than, or equal to, 70, and has a low shear viscosity (Eta at 0.1 rad / sec) less than, or equal to, 100,000 Pa DEG sec. The invention also provides a composition comprising a first composition, which first composition comprises the following: A) a first interpolymer comprising, in polymerized form, ethylene, an a-olefin and a nonconjugated polyene; B) a second interpolymer comprising, in polymerized form, ethylene, an a-olefin and a nonconjugated polyene; and wherein the first composition has a Mooney Viscosity (ML(1+4, 125 DEG C)) greater than, or equal to, 70, and has an [Mw(abs)] / [Mw(conv)] less than 1.2.