I have the Optima red top in the right side of the trunk. No problem after 5 years. Yellow tops are deep cycle, I believe, and are not suitable for a car. Mine has even been low after storage but seems to pick up and stay after charging it up.
mine turns over sluggish once in a while after sitting more than 2 weeks which i try to run every week,,red top,,battery cutoff,,3 1/2 years old,,but after running warm up charged and ready to go.spins the motor like new.we'll see what its got when i put the motor back in at christmas after the cam/heads change... sitting for almost 2 1/2 months,,now,wheres that volt meter??