It really depends on your usage pattern and what you value in terms of additional benefits. The prepaid plans usually skimp on benefits or premium services like VoLTE, WiFi calling, WiFi hotspot access, tethering, Visual Voicemail, etc. You will need to do you own research, read the fine print carefully and weigh the various bennies (or absence thereof) to understand the full picture of what you will get and what you will not get. Finally, you can decide whether or not any given plan is will work with your regular phone behavior.
As mentioned above, prepaid users are usually deprioritized on crowded cellular towers and are amongst the first to get degraded service (along with MVNO users like StraightTalk customers who also connect to AT&T's towers). If you don't come close to your cellular data thresholds like me, this is usually not a problem.
I bounced around on various prepaid services until I landed on my current T-Mobile prepaid service several years ago, a plan that has been discontinued but I'm grandfathered in. It comes with unlimited international texts and unlimited cellular data (first 5GB at 4G speeds, then throttled down), plus 100 domestic voice minutes for just $30 per month (plus $2.50 now in additional California access fees & taxes). There are almost no fringe benefits and tethering is capped at a measly 100MB. I have never come close to either the voice usage threshold or cellular data threshold.
This T-Mobile prepaid plan is useless overseas, but that's okay, I buy cheap prepaid SIMs from local carriers and shove them into my phone. I use Google Voice, so I can actually handle voice calls over their cellular data. It's not particularly streamlined, Google Hangouts for free outgoing VoIP calls and Talkatone VoIP for free incoming calls, but it does work. No one back in the States can tell that I'm overseas.
I just checked StraightTalk again, their unlimited nationwide talk/text plans are $45 with 5GB of high-speed cellular data (throttled after that) or $55 with 10GB (again throttled after that). If T-Mobile ended my grandfathered plan tomorrow, I'd switch back to StraightTalk's $45 plan.
Prepaid plans do not favor heavy cellular data users, but for someone with modest usage patterns like me, they can be an affordable and useful option. A lot of postpaid service plans are more advantageous to households with multiple lines and a mixture of users with a variety of cellular data usage habits.
I happen to be single, so my scrutiny of cellular service plans only takes into account my particular usage.
Long ago, I used Pay As You Go service (AT&T GoPhone), so I was paying for what I used, rather than a chunk of what was allotted to me. Some months I paid more, other months I paid less. It was working out great until AT&T restructured their GoPhone PAYG offerings and it no longer made financial sense based on my usage habits (I likely was not the only one who had discovered idiosyncrasies with the GoPhone offerings that made it a cost-effective solution).
The main takeaway here is to review various prepaid plans and see how they dovetail with your own usage. For most, it's better to find a plan that matches your normal habits than to force change on the user.
