X2 on what Chum Lee stated, do as much research on the various powertrains available for class A rigs and get out and view/drive as many coaches as you can get your hands on. We took our time and looked at coaches in surrounding states eventually driving nearly 1K miles to purchase our 40' class A.
These type of queries will get responses in favor of the rigs currently owned by responders, just good ole human nature and our need to feel superior. Not to mention some of the blanket statements that are simply farcical, best to take responses with a grain of salt, don't rush and enjoy the experience.