The new Zvezda kit is the only early to mid-1944 Factory 183 T-34-85 kit available, so if you want to depict an Operation Bagration period vehicle, it's the only one out there. The others depict tanks built during the final six months of the war. Zvezda's kit has plastic mesh for the engine deck screen (best replaced with photoetch) but the grills above the engine and on the sides are molded solid, with very little depth, and really need replacing. The two swiveling vents underneath the screens are molded closed, which isn't wrong, but unusual in summertime, unless the vehicle was under artillery fire. The fuel canisters have chunky detail, and the end caps are concave, as seen on some preserved vehicles, but period photos always show flat end caps. It also includes a large field stove bolted to the upper tail plate. I have only seen this in two photos, so it seems to have been uncommon. I left it off. The gun barrel has a separate end cap, but the joint is messy, so I used a metal barrel.
Dragon, as mentioned, offers a very late T-34-85 from Factory 183. If you get one of the boxings with photoetch and Magic Tracks, it's a very reasonable representation. The top and side grills are also molded solid, but the indentations are deeper.
AFV Club offers a fairly late model Factory 174 tank with its characteristic wide turret.
Academy offers a late or very late Factory 112 version (two turrets in the box). Biggest drawback is the molding of the front plate, which should slightly overlap the side plates. Instead, it's short, with a corner joint filled with weld bead. Also, the weld bead around the cupola is shown as a raised, rectangular-section rim. It needs to be sanded down and textured to look like weld bead. I have not looked at their Factory 183 version.
Italeri's new T-34-85 with interior mixes mid and late production Factory 183 features, and lacks the finesse of the AFV Club kit.
Have not seen any ICM T-34's, but reviews have not been promising.