I think the big difference is the OP is adding a front mount snowblower. That's a high dollar item.
To the OP, where did you get your quote? You have a couple of LS dealers within an hour or so North of you (Ranmar, and Sullys). Comparison shopping isn't a bad idea. I shopped both of them, and was very happy with both. I went with Sullys (closer to me being up North). They couldn't match the price of Ranmar (which was basement low) but they were willing to throw in free delivery for any warranty work that might arise, which was nice as I have no way of hauling it. Luckily, I haven't had to take them up on it in 1.5 years.
I will second Avenger. I heard the same thing about the frequent regen on the Shibaura engine. That would be a deal breaker for me, just due to the annoyance/hassle of it. I have the same XR4100 series as him. I always run at 2,000+ RPM. Mine only regens on the 50 hour mark (which is automatic if it hasn't done one on its own already).