I second the tripod issue, so if you are using a tripod, by all means use the SG!
On the other hand you are very limited in the amount of frames you can take, at least much more than with the RZ. The RZ and 110 re a great combination and produce some fine negs. I usually take my RZ over my 4x5s in cities, since you never know when you have to 'sneak in' a frame and for me setup is just faster.