Funny how when the season turns to winter how the conversation turns to generators.
Getting back to the original question, the proper answer is
it depends. Each of us have different needs and when a tractor comes into the decision, its characteristic also has to be considered. Things to consider for going with a PTO setup is, what's the likelihood of needing the tractor for other things and if that's the case, how frequent. The other thing when considering a PTO setup is, how good of a job does YOUR tractor do in maintaining speed as loads change. Some thing aren't sensitive to freq drifts and other things are pretty sensitive. The things that are sensitive are things with induction motors (motor that don't have brushes). Induction motors are likely going to protest being run say 10Hz off the rated freq needs. Equipment that could be affected are things like your refrigeration appliances, blowers/fans (think heating systems), compressors, well and sump pump and similar things.
As for a stand alone generator, fuel is a consideration. I'd rule out propane unless you already have a LARGE tank and temps don't get too cold if power outages during the winter months are a possibility. For gasoline, I've not ever had a problem with gas. As a matter of fact, I've been remiss in running the engines in our motorhome. MH hasn't been out of the shop for maybe 18mos and gas is older than that. This week when I tried to start the engines, both, chassis and generator, started within a couple sec and both were run for about 30 min. Have a number of other engines that are used infrequently and fuel has never been an issue. If you're concerned about leaving fuel in the tank, drain it. As to availability, if one has a few days notice of a pending storm, stock up beforehand. Oh, I do treat winter fuel with Sta-Bil. If natural gas is available and generator is fixed mounted, this might be a very good choice.
One issue I have is I don't understand the need of some saying they'd run their genny 24/7. This especially doesn't make sense if fuel availability is an issue. I've not had the need so far but if the time comes, I'll be using 2 generators. A small 1kW inverter that will see service most of the time and a larger one to be used a couple times a day for short periods to replenish the well water and cool down the refrig equipment. What we've always done during outages, we've always had advance notice, is to fill the bathtubs for water supply to flush the stools and wash hands. Will have a few gals of drinking water that will hold us over for a day or two if needed. Except for the heavy loads, we can get by on 500W of power. That will run the pellet stove, TV and all that is connected to it and keep the internet and computer running plus lights in several rooms. The little genny uses about 3 qts of gas over ~5 hrs of operation @ half load. The bigger one uses ~1 gal hr but it won't be used much more than an hr or two at most day. Don't need large qtys of gas to be on hand. Longest time we've every went without util power is 3-4 days and that was yrs ago. Here at the new place the longest we've been without power is maybe a day and a half.