I have had it about a week. I have run it every everyday on 4S and it is awesome. I am so used to my MERV that I was never able to get a full run out of because I always broke something first. My question is what parts can I expect to break first? I will likely buy upgraded replacements over the next month so when it breaks I will be prepared. Also is there anything that is absolute must to upgrade right now? I ordered Proline Trenchers.