I'm in a condo and have an old Murray 6 space 100 amp breaker panel. I'm remodeling my kitchen and want to add circuits while bringing the installation up to code. I'm planning on adding two quadplex breakers. These quadplex breakers consist of two 2 pole 20 amp common trip breakers. With my panel, this will allow me to add 2 MWBC per breaker or 4 total which would be the max for my panel due to the layout of the bus. Does anyone see a problem with this? Also, the prices online for this breaker vary widely with many (if not all) being "refurbished". I don't like the sound of refurbished but other than changing out the panel, what other choice do I have? Ignore the ratings on the handles in this particular image.