Medela symphony vs spectra s2

Hi, I'm looking to increase my supply that had recently dipped for reasons I can't seem to figure out. I'm 7 months ppd and I'm pretty much exclusively pumping. I've been using the spectra and I've been loving it until recently but I'm really thinking about renting the medela symphony for a month to get my supply up. Not sure if I should stick it out a little longer with my spectra or give the medela symphony. Anybody have experience with both?