After reading several threads and watching multiple reviews, I recently purchased an Umarex Notos to fill a PCP carbine niche in my small collection of air rifles, and I'm planning to modify it similar to this thread (
https://www.airgunnation.com/threads/i-sipped-the-notos-kool-aid.1299436/post-1593550) thanks to several posts there by other enthusiasts. The package arrived during the week, and I wasn't able to take it out and shoot it until two days after it was delivered. The rifle arrived already charged, but was about 500 PSI below full. After cleaning the barrel and mounting a scope, I sighted in and shot the carbine with my FX Chronograph. The rifle was shooting very well with Crosman Premier HPs, just like a lot of others experienced. I was very pleased with the carbine's performance right out of the box. I am planning to modify the carbine with a regulated drop block and CF bottle in place of the stock regulator and tube.
After shooting, I topped off the carbine to maximum pressure and set it against the wall in my office (conditioned space). Overnight, most of the air leaked out of the reservoir. It completely emptied by mid-day. I have contacted the re-seller and am awaiting a response from them. The carbine is completely stock, and the dealer is very reputable, so I expect a repair or exchange to be relatively easy.
Here's my conundrum:
All of the modification parts arrived today (plenum, drop block, and CF bottle).
Should I RMA the carbine for a new one that doesn't leak, or just go ahead with the modifications I planned to do anyway? These would be pretty significant mods on my part (in that I have only added a power plenum and tactical kit to an FX Dreamline - parts made by FX for their rifle). I don't know where the carbine is leaking from, but I'm guessing that there's a good chance my changes will fix the problem, since I'm basically replacing the entire reservoir and regulator system (including gauges).
Thank you in advance for any advice/insight.