We bought a Howse 500 (light duty) many moons ago and have beat the heck out of it ever since. The only major problem we have had with it is when we loaned it out. The person broke the shear bolt and replaced it with a Grade 8 bolt, thereby killing the gearbox the next time around. They replaced the gear box and it continues to run. We also noticed that the people who borrowed it turned the blades upside down for some reason. Would there be a reason to ever do this? In the process of removing the blades to put them the right way, we stripped one of the blade bolts. I ordered two new blade bolt kits for $11 each. Howse and King Kutter both seem to maintain a good parts history and inventory. The round shoulder blade bolts on my older model are a pain to tighten but they have since changed this with square shoulder blade bolts on their newer models.
Also be aware of the chain guards. Many economy models are priced without the chain guard, assuming you will provide your own or buy their kits. I don't think it is recommended that you use the unit without the chain guards so make sure you take this into account. For instance you can get a Howse 500 (5' RC) from Northern Tool for $750 but this does not include the chain guard. The chain guard kit costs another $150, which brings the total to $900 + S&H. A Howse 400 (4' RC) with chain guard kit would be $830 + S&H. S&H to Vermont on these units would be prohibitive. However, there seem to be several King Kutter dealers in your area so you should take a look at them. Have you got a price on a King Kutter unit yet? It appears a 4' King Kutter will be around $630 but I don't think this includes a chain guard. I'm not sure King Kutter even has a chain guard as an option so you may have to make your own. Maybe someone else will have some input on this. A $500 difference is a good chunk of change.