Nearly tier 8 with the Germans now, and it has vastly improved from the low tier Italian garbage. However the Stukas are mostly useless - slow, easily taken down, and overall outclassed by Su-2s and IL-2s. Although you can get a respectable loadout on some variants (2x 250kg and 1x 500kg), they are designed as dive bombers, so you obviously don't get bomb sights and don't have the safety of altitude. After executing a dive bomb maneuver you are basically a sitting duck for any enemy fighters in the area that are paying attention.
The Stuka G's have 2x37mm cannon which can take out nearly anything in 1-2 volleys, but the ammo capacity and ROF are bad. You don't get any bombs, so you are restricted to hunting down enemy bombers, and again the Stuka has poor speed and can't climb for dick. In fact if you ever end up down on the deck it is probably faster to land on an airfield, hold down J to get out, and reenter the Stuka so you spawn at bomber altitude again.
The Bf-109s so far are capable but not outstanding. Their armament isn't the best, which is a problem because due to their playstyle you can only get guns on target for 2-3 seconds at a time. Unless you are quite skilled and can snipe at people's wings, it takes multiple passes to get a kill, especially if the other pilot is aware that you are making a pass. But I'm looking forward to getting the G and K variants and the Fw 190s, as they tend to have ridiculous firepower. I also just unlocked pylons for a 500kg bomb on the F-4 and F-4/trop, which will let me crack a pillbox for free every 4-5 minutes.
Brits have great fighters and interceptors. Their early bombers are fairly weak and can only carry 2x500lb. I'm at tier 6 and the Wellington comes at tier 7 with a monster 4000lb bomb, so that will change things up. But the Spitfires and Hurricanes excel at dogfighting and have the right combination of speed, maneuverability, and firepower. Beaufighters are fast with sick firepower so they make short work of bombers and attack aircraft. There are a surprising number of people that try and dogfight in them though, so I like to keep an eye on enemy Beaufighters and prioritize them if I see them drop to low altitude. Tip, if you see a Beaufighter diving on you quickly, fly straight and then make a sudden turn when he is about 1km away. Their handling SUCKS and he will not be able to correct his aim before he blows by.
Soviets are still outstanding at tier 9. Great all-around fighters and attack aircraft, and easily have the best bombers, with literally a dozen at tier 3-8 that can mount payloads of 2x500kg, 3x500kg, 4x250kg, 6x250kg, etc etc. I uploaded some Yak-9T gameplay for anyone that wants to see what they are like:
http://www.youtube.com/watch?v=rtAuegGj4zg