Lemon wood will make a reasonable heavy bow however the performance will not be like that of Osage or Ipe, that is due to the fact that both Osage and Ipe hold a lot of draw weight for very little mass, this will speed up the limb return, however lemon wood is perfectly adequate for making heavy bows and will have no trouble reaching clout distances and innevitably ranges up to bow shot 240yds when using the correct matched arrows. A bow that takes on a bit of a set usually proves to be more reliable so as long as it is a little ammount then don't worry about it, The dimensions used on the DVD allow for this and keep the tips quite stiff, this will reduce the ammount of set, also gluing with a forward set will greatly reduce the ammount of set. This is all discussed on the DVD.
Other woods that can be used for the belly are:
Costello Boxwood
Jatoba
Pau Amorello
Satin Bloodwood
Santos Rosewood
Ipe is very cheap in comparion to the other woods and can be bought as lengths of decking, however you must clean thoroughly with acetone before gluing as there a lot of natural oils in this wood.