I bought that mixer a few months ago. I like it a lot--especially the eight quart bowl, open bowl handle, power, what looks like cast stainless steel paddle and dough hook (they are really heavy) and NSF rating. I could have gotten a refurbished one for about $200. less, and if I had to do it over again, that is what I would choose. The refurbished model does have a shorter warranty. A bowl shield is not available, and I bought a generic pouring shield on Amazon that works well.
While it was running, I had my hand on the speed control a few weeks ago, and it just stopped when it should have been running. That alarmed me, and I contacted Kitchenaid, and asked if that had been a problem. They told me that I could ask for a replacement, and they would send one out immediately. I decided not to, but I will certainly keep my eye on it.