I don't understand what you're asking. Of course it is. If you just want cheap telephone service in your home, or even a somewhat featureful VOIP PBX for your 1-2 employee small business, then the cloud solutions are best.

If your goal is to learn VOIP, or you have a larger business, you're now looking at $200+/month for 10+ users. That starts being real money.

Even if it's just a personal setup, and it takes you say 4 hours to setup a per-minute voice setup, $10 less per month is $120/year, and a setup like this could easily last 3 years, now you're looking at $360 savings for 4 hours work. Not too bad at an hourly rate, and that's valuing the learning and fun of setting up such a system at $0.