There is space for a large suitcase but it depends on the suitcase.
The hubby and I currently have a large duffle bag, five medium boat bags, two computer bags, a cooler, and various small bags in our GP as we kick off MTTS.
Might want to go check your local Bass Pro for some boat bags, they make great boot bags too.
Stereo speakers are only in the front.
The GP is the hubby's car but we are both very happy with it.