I have been using MacUpdate Desktop on and off for several years, but have never been thrilled with it. For $40/year (they sell it as $20/six months for some reason, presumably to make people think it costs less) there was very little progress on the app or service.
Although the MacUpdate website is a nice service for the community, the app itself is not great.
A little over a year ago I came across MacUpdater which is a much better app, and which finds many more app updates. The best part is that the app is a one-time fee of 9.99$/€ rather than a subscription.
The app has been very well supported and regularly updated, and I can heartily recommend it.