I bought both of my 4runners through them. a used '99 in 2004 and a new 2013 in 2013. Sale experience was good, price was good, nothing stellar but a good experience.
Heed caution when using their service center. Just check their work, nothing catastrophic by any means, just annoying avoidable wastes of time.
They are super friendly and have a real nice facility, the quality of work and attention to detail is... well.. sadly to be desired.
Most recent experience, my 2013 back camera went out, I took it in under the "master tech" insurance. I started of with the typical phone call giving the specifics about the issue. I drop it off before work. Time goes on, I get the late afternoon phone call. "Yes, the camera is bad and we need to keep your car overnight" huh okay... first big no no, no offer for loaner. Fine whatever.
They replace the camera sometime during the day, no phone call, I call at 4:00pm, "oh yeah yeah come pick it up it is ready sorry we're real busy" LOL wtf? How long has it been ready? It is five blocks from work so I head out pick it up. No one there, as in they aren't busy at all. Again fine whatever. Pay the $50 deductible, had the safety/emissions/reg done too, grab the stickers, check the camera it works, and go.
I go to put the stickers on the plate, huh that gap wasn't there before, the rear 4runner trim now bowed out a bit. I open the hatch, the trim, wtf, sharp object to remove the trim? Seriously? buggered the paint and marred the trim, now the rear door trim doesn't sit flush.
I bring it back, 2 hours later, I get the well we tried, and we cleaned up and buffed out the scratches the last guy made. I look at it, the exterior 4unner trim sits better, the interior trim still bad and now with a new mar in it. Does these guys use trim tools?
I get home and take it apart to check for myself. When the service manual says "non-reusable part" you kinda expect they won't reuse it. Righhhtt... Well the butyl and visqueen that seal the access for the backside exterior trim, all fk'd up now, it is a mess, most not even clinging to the metal anymore. Yay more dust in the truck, glad I checked it.
I just wish they would give me the part to fix this stuff myself.
Second: couple of years ago I went in for the final "Toyota Care", I told them specifically which schedule to follow, I only had 15K on the truck at the time but it had been 1 year, so one year service, most important part of 1 year service? Change the oil and filter, what didn't they do? The 1 year service OR change the oil and filter, they did 15k service and called it good.
Again I dropped it off in the morning, no progress call, they called me at 5:30 to pick it up. I look through the paper work... huh wait, where is the oil change? "what oil change", "the one I instructed you to do", "oh uh, we'll get that done right away". Oh great I am going to get a nascar 30 second oil change, yep, as I watch that is what they did, come button up I see the pit tech grab an impact wrench and rattle gun my skid plate bolts in, no hand start, WTF and what did he do? cross threaded one of the four.
Again super friendly, yet fast and pretty unacceptable service.
Third: Before this 4runner I had a 3rd gen 99' SR5. Loved that truck, anyway as with lots of 3rd gens the steering racks have a tendency to go out (I wish I new that back then) It is mid December, cold as hell, I don't have a garage, only a carport. Well my rack finally gives out, not going to brave a job I have never done without a garage. I took it to Mark Miller being the closest dealer to me. Get a new rack and flush, well three days later the rack goes out again, I bring it back, they replace it, and charge me for fluids and labor? What? okay whatever. I should have known back then this place has strange operating principles.
tl:dr I understand that no one cares more about my truck than I do. Mark Millers staff are both nice and friendly, sales and service. If you have a lease or you trade your cars in every few years, you will never know the difference. Maybe they just work to hard on volume, don't know, don't care. I would prefer a better end result. On the other hand, if you expect any form of quality work, I would suggest you look elsewhere.