MANDOBLE,
The Ju188A-1 is faster than any of the numbers I've seen for the He177. Ju188A-1 could do 325mph, the He177A-5 is listed at 295mph or 305mph in my books.
The intrim Ju188E series might have been slower, but those were just a stop gap until the intended engines were available and production of the Ju188A series could begin.
Armament wise the He177 is marginally better than the Ju188.
Looks wise the Ju188 blows the He177 away. In fact the Ju188 is quite possibly the best looking bomber of WWII, at least IMHO.
Ju188 dataHe177 dataI do think that the He177 would replace the B-17G as the most common bomber in the AH MA though. It carries nearly the load of a Lanc while having nearly the defensive firepower of the B-17G and is faster than either.
The Ju188A-1's speed, bombload (3,000kg {6,614lbs}) and armament would certainly make it popular as well, though not as popular as the B-17G.
I know that I would use the Ju188 far more often than I would use the He177.
I think that either would be nice additions to the planeset. Personally I would prefer to see the Ju188A-1 and Tu-2S added rather than the He177A-5.