As much as I like the Bf-109F and Bf-109G from Angels 20, I typically find myself passing on them and sticking with the Bf-109E Ace in most competitive games. The reason is simple - firepower. Against any mid-late war planes, the F and G simply don't have the firepower to be competitive. I believe this is because RB designed the card to reflect the baseline armament of these models, which didn't include any large guns in the wings. This resulted in a real-world criticism of the planes by top German pilots, and lead to a number of field modifications, known as Rüstsatz. Among them, the Rüstsatz VI modification added two 20mm cannons in pods below the wings. It had some impact on the planes' performance, but the added firepower was seen as more valuable by many pilots, particularly those facing Allied heavy bombers. This is my take...
The Roll penalty is there to reflect the impact on maneuverability that I think needs to be present with the added firepower. It fundamentally changes the cards and makes the highly situation Bf-109G Gustav Ace pretty nasty. I'm not convinced 3 points is high enough for the card. I might end up increasing cost to 4.
I'm also considering putting a year limit on this card. I haven't been able to nail down the first time it was used on an Bf-109F, but it appears to have been pretty common on the Bf-109G. 1942 might be a decent introduction date and prevent to the Bf-109F from becoming too much of an early-war monster.
I wish to have no connection with any ship that does not sail fast; for I intend to go in harm's way. - Captain John Paul Jones
It would give the G the same guns as the E (7/4/3) instead of the guns of the FW190D (7/5/4). The G is still going to be devastating IF it can pull of a Range 0 shot, but hey, it's supposed to be awesome (and currently isn't)...