a little more fuel to come up to temp probably.. is my guess.. I use about a 1/4 bag of charcoal and 2 splits to get my Traditional up to 300 in about 45 minutes.. in the summer and 1 hour and 1/4 in the winter time.. or if it is cool outside. Since a RF you need to heat the baffle.. and start your draft which is a lot longer route Vs. Traditional for the heat and smoke to travel... My guess is it would take more time..
^^ My Build
Building a Fire in an Offset 101