All of them silly, if you make your tanks twice as heavy but call them something else so everyone compares apples and oranges your tanks look better. [:D]
Light tanks
Vickers Light tank (.50 cal)
Panzer 2 (20mm gun)
M3 “Stuart” (37mm gun)
T70 (45mm gun) all have light armor.
The Soviet and US tanks easily out match the German design, Stuarts were challenging Panzer 3 & 4’s in North Africa, the underdog but still dangerous to German mediums in '42.
Early war mediums
Crusader (40mm gun)
Panzer 3 (50mm gun)
Panzer 4 (Short 75mm gun)
M4 “Sherman” (75mm gun)
T-34 (76mm gun)
Again the US and Soviet tanks, outclassed the German tanks
Late War mediums
Cromwell (75mm or 6 Pounder) Shall we even mention the Firefly and Comet?
Panzer 4 (75mm gun)
M4 “Sherman” (75mm or 76mm long barrel gun)
T34 / 85 (85mm gun)
Here things are fairly even, the German 75mm was a better anti-armor gun than the US / UK 75mm, but the 6 Pounder, 76mm and 85mm were clearly better and all had equal or superior armor than the Panzer 4 by this point, all were also better mechanically.
Early period heavy tanks
Matilda 2 (2 pounder)
KV1 (76mm)
Tiger (88mm)
Ok, here the Tiger is pretty clearly the winner, although the KV1 could give it a run and the Tiger just barely qualifies as early period.
Late period Heavy Tanks
Churchill (75mm gun), not going to count the Centurian as it saw little to no use.
Panther (75mm long barrel gun)
M26 Pershing (90mm gun)
IS2 (122mm gun), similarly not including the IS3 as it is debatable if it actually saw combat
Tiger 2 (88mm gun)
Of these 5, the Churchill is clearly the loser, good armor but very weak gun for a heavy. Among the rest it is not so clear, the IS2 had good armor and a decent gun, but also a very small ammo supply (about 1/4 that of its German opponents), the Panther and Pershing are fairly evenly matched, gun and armor probably going to the Panther but mobility and reliability going to the M26. The Tiger 2 definately the most powerful of the 3, but its mobility and reliability definately falling short or both the M26 and Panther. In the case of the M26, IS2, Panther and Tiger 2 the first hit could easily determine the outcome, none could expect to use its armor as a primary defense against any of these guns. Personally from a combat only perspective I’d edge towards the Panther, followed by the Tiger 2 or IS2. From a “big picture” (logistics, getting to the battle etc) I’d go with the M26. Both the Panther and M26 are more along the lines of the Main Battle tank, the heavy tank concept dies fairly soon after WW2 because they are not practical.
So outside of the heavy class, the only tank designs the Germans consistanly out performed were the British. Since the British never really produced a light or heavy tank resembling the German concept, this is not surprising. In the medium category the British produced roughly equal tanks, arguably inferior but effective early war, and possibly superior but closely matched late war. US and Soviet tanks were more than capable of killing their opponents of like classification throughout most of the war, the German mediums probably led the Allies for a brief period in 1943 prior to the adoption of the 76mm in the M4 and the 85mm in the T34.
Of course this is all my opinion, and its silly to expect tanks to be classified against their similar counterparts in number and weight class (+/- 10 tons). I mean we all know that most of the German tanks were Panthers and Tigers (Panzer 2, 1800 built, Panzer 38t 1400, Panzer 3 5500, Panzer 4 8500, Panther 6000, Tiger 1300, Tiger 2 500, number per wikipedia, tanks only no SP guns included). Total german tracked armor all types 50,439.
Some other fun numbers Total T34 production 57,000, total IS2 production 7600, total M4 production 50,000 +/- (can’t find a firm number ranges from high 40,000 to high 50,000) total M26 production 1400.