I enjoy my Stanwell greatly. It was one of my first pipes and I got it from P&C. I've had over a dozen orders from them over the last 6 months with great success. The two small issues I had were handled quickly and easily by them.
The questions you're asking, most of them, are ones that the pipe community has debated forever (moisture level, filters, estate vs. new) and will surely continue being debated long after your first purchase.
So, find one that appeals to you and jump on it. Worst case scenario is that it will be an OK smoke instead of an awesome smoke, which is bound to happen to you sooner or later, anyway. We all have some OK pipes and some awesome ones.
I see what Ben is saying concerning estates, but, as a new pipe smoker myself, I'm going to agree with MSO and recommend the new pipe. Some of the estates I've gotten were great pipes that allowed me to learn pipe care at a moderate pace, but a couple were ghosted nightmares that required "extreme measures" and would have deterred me from pipe smoking if they were my first pipe.
Bottom line is, you can't go wrong. Each choice has its pro's and con's.
Welcome to the forum!