Using Videopad since V8x, we've not had many problems with the 'professional' / 'master' version, as long we only imported just a few (only the most necessary) video and audio tracks such as for adverts or trailers. As professionals, for bigger projects we use something else. We bought and played with VP and found that it's easy to learn and get along with. A simple video production is easily achievable with VP. Unfortunately we can't justify the full version price, issues, taxes etc. VP is not our go-to software, not least because it's only 32 bit (VP sorely needs a total overhaul imho).
We don't have time for proxy editing. There is no option allowing you to reduce resolution previews (a staple feature of video editors weirdly taken out of VP). I guess the bottom line is that time is money for professionals and customers (or even for private users), but Videopad works just fine within a specific user base.
That's our frank, honest and balanced answer to the O.P.
Have a great day.