There are differences in the finished product depending on the construction method. The pattern usually dictates which method will be best, but in some cases the desired outcome will be the deciding factor in using lead came or foil.
The lead came method only requires three steps: cutting the glass, assembling the piece by fitting them into the lead channels and soldering the channels at the joints to hold the glass together. Lead came results in straighter, more uniform lines between glass pieces. Simpler designs with larger pieces are usually done in this method.
Foiling requires an additional step of wrapping each piece of glass with foil tape before soldering. The lines are more irregular and in some places intentionally varied widths give character to the final outcome. The required extra step of wrapping the foil and working with smaller glass pieces results in a more expensive finished piece. However, more detailed designs can be achieved using this method and the cost is well worth the outcome.