I haven't looked at the current model but the last time I looked, the answer was no — the top end and lowest models have the same cleaning engine and the only differences were convenience features, most of which were really minor. I ended up with a low- to mid-model.

I agree.

Use naptha (lighter fluid). Works very well, non-explosive, and damages very few surfaces. On the rare occasion when naptha fails, turn to Goof Off, but be careful. It damages some surfaces, especially plastics.

I think his advice is to hone it on a steel before each use. Takes a couple of seconds.

You're not in yet. There are generally other candidates in the second interview pool, and the second interview often includes interviewers you did not see the first time around.

Is there an emoticon for rolling eyes?