What do you mean by 'comfortable'?
In most cases when people mention the 'the dealer is more important' there are objective criteria for evaluating the dealer that make you 'feel comfortable'.
There's no way to put a dollar figure, either a percentage or in absolute numbers, on the dealer. It will be different for everyone since a person's tolerance for a poor dealer is usually inversely proportional to their skill in servicing your own tractor. In other words, if you are mechanically inclined and will, by and large, treat the dealer like a parts store, how 'comfortable' you are with them is almost irrelevant. Some dealers even allow you to order parts online, so you don't even have to enter the store after the purchase.
Listed below are some objective criteria to evaluate your dealer...
When you're at the dealer;
Check out the service area. Is it clean? Are the mechanics working? Does it look professional? Or are people standing about drinking coffee and talking? Do the mechanics wear uniforms or are they dressed in jeans and T shirts? See any trucks and trailers owned by the dealer indicating they do pick up and delivery? How many of them are there? Big enough to handle your size tractor?
Check out the showroom/sales area. Clean and neat or a pig sty? Some manufacturers have dealer awards for sales and/or service. See any hanging on the wall? Are there empty desks in the sales area? If so, why are people leaving? Do they sell attachments? If so, are they major brand name attachments or no name ones? Some major brands have dealer requirements such as stocking a certain number of models and parts to fix them. If (fill in the blank of a major vendor) is willing to trust these guys, they are probably OK.
Does the place look busy? Not so busy that you're ignored, but busy enough to know that other people trust and like the place.
Walk around the outside. Is there used equipment for sale indicating recent trade ins? Is there a good selection of new tractors and attachments? Are some of the new tractors equipped with a FEL so you can see how they look and try them out? Do some of the tractors have attachments on the three point hitch so you can try them out as well? Is there a paved, grass and dirt area for you to test drive the tractor? Will they loan you a tractor to try out on your property?
Check out the Parts Department. Lots of shelves of parts behind the counter? If not, you may be waiting if you need one. Check the shelves on your side of the counter. Are there any? Bolts, nuts, paint, oil, pins, i.e., the odds and ends and consumables a tractor needs.
Does the dealer sell other things, e.g., Ag tractors or other large farming equipment, lawn and garden tractors, chain saws, string trimmers, things that indicate the dealer is a thriving business. This can also be a problem, i.e., the dealer is a jack of all trades and a master of none or that they concentrate on their large farmer customer base to the detriment of their other customers.
Does the dealer have separate departments for each line (Large Ag, Compact, Lawn and Garden) of equipment they sell and service with separate service trucks?
Check out their web site, assuming they have one. Professional looking or are the Copyright dates still 2003? Send them an email via their web site. Get a response?
Call them on the phone. Get a cheerful receptionist or Bubba back in the garage. Or do you descend into a phone system never to emerge? How many times does the phone ring? Do they have toll free numbers?
Do they take credit cards? Do they offer local bank financing?
None of these things are fool proof. Mechanics can wear uniforms and still be incompetent. People can be friendly and still give you a raw deal. Just some things to think about as you visit each dealer. All of these things help you form an overall opinion of the dealer and what kind of support he will provide.