yeah it needs new engine mounts... its not an easy swap, but its acheivable with the proper information, money, and time.
there is a write up about the engine swap over at mustardcats website here:
http://mustardcat.brinkster.net/
as for speed, i think they are quite fast because theyr lighter than a 4th gen lude. I think it puts out about 100KW at the wheels, which is a big improvement over the 65KW ATW that the B20A produces