Maytag and GE (General Electric) make the best. They are by far the oldest manufacturers and that should speak for themselves. They also offer incredible warranties that just make buying from them more secure.
It seems like Viking is a pretty reliable and trustworthy company with great reviews on their gas ranges. I would look at those or R.H. Peterson Company.
I am sure to say Lowe's company is the best option for a 30-inch gas range.They always offer for low prices and free shipping.They offer for no interest charges for one full year.Lowe's is the best company for everybody.