We have 2 Ariens service shops and a Dealer in our little town, which is another bonus. I can have the Ariens shipped right to the Dealer who will assemble and test it prior to my picking it up. It is a hard decision, we don't mind spending a little more if it means less chance of issues.
I would definitely recommend purchasing from an Ariens dealer over Home Depot. My HD Ariens arrived crated, empty of hydraulic oil, and missing parts. I spent most of the money I saved at HD on hydraulic oil, not to mention the time wasted trying to find a place where it could be purchased. Neither HD nor Ariens responded to my calls for help, though admittedly I was aware there was some chance that the oil wouldn't be provided and the missing nut was replaced with one from my parts drawer. A bigger concern is that both companies said they would do something and then ended up doing nothing, and I'm left with the feeling they just said what was needed to get me off the phone. My closest Ariens dealer is 75 miles away, so using him is possible but inconvenient should the need arise. The fact that he is available matters a lot to me because I can just imagine the cluster f*** that would arise should I attempt to have a splitter repaired at TSC or HD, let alone a mail order outfit like Northern Tool.
Many folks have praised the Subaru engine in the Ariens splitters, and so far mine has always started with only one or two pulls, even when I run it all the way out of fuel. Honda gets high marks as well. Briggs engines still grace the splitters at my local TSC, though I think I read somewhere that they are switching to Kohlers. I'm not real keen on either brand, but again lots of people have been happy with them.
Almost all the smaller oaks here had been cut two to five years before I bucked and split them, and popped apart after just a few inches of wedge travel. If your oak is anything like mine, that means you can short stroke the ram and save a lot of time waiting for it to come back down from fully retracted. The 34 and 27T Ariens move more slowly than my little 22T, but if you short stroke it the difference is probably pretty minimal.
The one or two oaks I had that came down in the last year were real bears to split, stringy and tough, making me use the wedge almost like a cleaver to cut across twisted grain that just wouldn't come apart any other way. Better to have the added capacity and not need it than the other way around.
I think my biggest round was about 18" across, and it took all I had to lift it up onto the rail. Only had two or three like that, but if I'd had more I would have tipped up the splitter and just rolled them onto the foot. I think the 34T Ariens will operate horizontally or vertically as well.
It sounds like you have the right idea buying heavy duty, reputable equipment to tackle those trees. All those checks and splits in the logs in your photos have me thinking you'll have no trouble getting them to split no matter which of the TBN "favorites" you end up with.
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