All the engines are worth what you pay for them. Every one.

Some obviously cost more, some are cheap. All will work for someone with experience. Usually.

What it boils down to, is that every one is a gamble, but the odds are set by what each one costs. The cheap ones are more of a gamble. The more expensive, the less the odds that you're going to wind up with a clunker. You pays your money and you takes your chances.

With the more popular and more expensive engines, there really isn't much risk. For example, OS and Saitos are no real gamble at all. And any engine that's as universally used as most OS are is obviously going to do what you want. And do it for a long time.

Everything we buy in this hobby is a gamble. Some just aren't much of a gamble at all. And if your certain purchase happens to clunk, when you've bought from a quality mfg, you're still not going to lose the bet. They back 'em up, no bet there.