The Seneca is a nice 'hawk: VERY well made, kind of large. The forging appears seamless, and the fit to the handle, very tight. It seems to be an immaculately-made hand-forged tomahawk.
The sole issue I have with H&B Forge tomahawks is the thickness of the blade, and (relatedly) the abrupt obtuse edge grind. (I've worked on this on mine by slowly convexing the edge with a belt sander, cooling frequently with ice to prevent drawing the temper.) This thickness has to make the hatchet very hard to break. It also makes it kind of heavy. The tomahawk I see as the main, same-price-level competitor is the Fort Turner Buck Hawk. They're roughly the same size; the Fort Turner has a broader blade that protrudes up above the plane of the top of the eye. The biggest difference is that the Fort Turner blade is MUCH thinner. This makes it easier to sharpen, probably easier to stick when throwing, and probably easier to make a deep cut with a single chop. It might make the Fort Turner more likely to bind or stick in the cut, too. The Fort Turner hawk I have looks a little more rustic and appears just a little less exquisitely-perfect in fit and finish than the H&B--which is not necessarily a bad thing. The Turner 'hawk is also a lot lighter, and "faster" in terms of maneuverability. I do wonder, however, if it might be a lot easier to actually catastrophically snap a Fort Turner blade than an H&B one. I've never done it, and have never heard of anyone who has, but that very thin blade just looks like it might be more vulnerable to a bad blow against the rock-hard wood we have out here in the desert, than the H&B one. I've had spectacular, bend-over-backwards customer service from Fort Turner's proprietor, Dana Turner. The handles of the Turner 'hawks are coated with a shiny varnish; those of H&B are stained and, I think, given a dull linseed oil finish. The handles of both have a "teardrop" cross section, with the angled part toward the front. With the H&B 'hawks, this angle is pretty acute; with the Turner, it's more rounded. My wife likes the roundedness of the Turner--more comfortable to hold. Also, the H&B handles I've seen are uniformly VERY straight of grain--which I think makes them stronger; the Turner ones I've seen have a little more diagonal grain going, which may make them easier to break. I have yet to break either, myself.
They're both great hatchets. You might enjoy getting one of each, and using and comparing them side by side.