Knowing Mike and having watched him in action, I would say he is for the M8000, not against it. One reference bears expanding -- packing line on the drum in the real world.
The M8000, as well as the 9.5ti and every one of the tabor line I believe, use a lay down drum design with support rods between motor end and gear case end of the drum. These rods limit how much of your line can be packed onto one end of the drum during use without stopping to unwind and rewind the cable so as to lay flat. All horizontal winch designs share this same limitation.
The 8274 does not. It has an open drum design which uses a foot-forward mount to support the light end of the drum so there are no cross rods. You can pack as much line or cable on one end as space will otherwise allow.
Admittedly this is not the best way to winch for several reasons. But in the real world, it is often better to allow the cable to pack on one end for a few more feet than to stop, release pressure, unwind, unsnarl, and repack the drum, just to get a few more feet before having to stop again. This happens with off-angle pulls of long duration and can not be helped. The 8274 is about the only winch on the market that is relatively immune to this problem. I have made full length, off line pulls using 160 feet of synthetic line (150 usable) without stopping. You can't so this with the M8000 or the Tabor, nor with the other brands of similar design.
This feature is particularly attractive to severe duty installations and for off road racing where time is the killer and you can't take time to fool with winch rope. For general use, it is not an issue.
Since you will be doing mostly light to moderate duty winching on only an occasional basis, you don't need a killer winch. As you say, you need one that will work when needed. But, the only way to avoid surprises on the trail is to test your winch before starting out, each and every time. That means that before each trail ride, you spool off all the cable or rope, check the drum surface for debris or corrosion, check the line for kinks or frayed spots, check the electrical connections and power cables, check the controller for function (which in turn checks the solenoids for function), then repack the line. It is a PITA to be sure, but is easier to fix problems in your driveway than deep in the woods. At that point, you will know that no matter what brand you have and whether or not it has seals on the drum, it works.
As for the size, the M8000 is rated to pull 8,000 pounds single wrap. So is the 8274-50. My CJ7 weighs 5,300 pounds loaded for the trail, and the 8274 will pull it up and over anything. To compare, I recently mounted an M8000 on my early CJ5 and took it out in the woods to reset the new winch cable. It pulled bottom of the hill to the top, full length pull (125 feet) with only a couple of stops to turn the steering wheel so as to load cable smoothly, without the need to stop to let the motor rest or to recharge the battery. It pulled fine, was plenty fast enough, if not quite as fast as the 8274, and help the vehicle on the hill without slipping. It pulled as well fully wrapped as it did on the first wrap, but of course, I was not stuck, the CJ5 is only around 2,500 pounds, and the incline was moderate (25 degrees or less). You need to keep in mind that no matter what your vehicle may weigh, it never takes that much pull to get it rolling unless it is wedged in the rocks, buried to the roof line, or being pulled vertically. Rolling loads are always far less than static weight, and most winch pulls are in the 2,000 pound load range, even with 4,000 to 6,000 pound vehicles.
Personally I believe the 8274 is under-rated in terms of load capacity, but still the 8274 and the 8000 are close enough in capacity to make some comparisons. The M8000 pulled 2,500 pounds like it was a butterfly. I would expect it to pull 3 times that much weight using care and patience. If I can get by with 8,000 pounds of pull on a 5,300 pound vehicle in race mode, you should find an 8,000 pound winch more than sufficient for 4,500 pounds in expedition mode. In the alternative, the 10,000 pound Titan should be able to pull you up a tree, and the price is more than competitive.