Mako Spearguns is a great brand for beginners looking to start spearfishing. In fact, the Mako Predator Pro 3G speargun is one of the best on the market in it's price range. Of course, I'm a big advocate about buying the best speargun you can afford, but there's a massive market for cheap spearfishing gear, and that's where Mako Spearguns fits in. Because you shouldn't have to spend hundreds of dollars on spearfishing gear when you're just getting started.
Now, their spearguns aren't top of the line, but comes with the price tag. They're produced cost-effectively in China, and what Mako Spearguns does really well is their customer service team. They're top notch, and will give you all the information you need to get in the water and start spearfishing. Honestly, you don't need a thousand-dollar speargun if you're just going to flap around on the reef and try to spear some fish.
I've used my fair share of Mako Spearguns, and in my experience they hold up well for a couple of seasons, maybe more if you take good care of your spearfishing gear. But don't be discouraged if something does break. At half the price of most other spearfishing gear you can't expect a Mako Speargun to hold up over time. What they've mastered is providing a cheap speargun to introduce newbies to the sport. You can always upgrade later once you've caught the spearfishing bug.