They are all generic toy quality/lowest quality, lowest cost mass produced junk lasers made by several factories in China.
What do you expect for about the price of a good cup of coffee $5-$10 retail price on eBay, shipping included.
Just keep in mind that the cheapo 303s and 301s are generally all over spec. So you aren't getting something <5mw. Safety goggles are a necessity. Also if you decide to go with a 532nm they usually will leak IR light, which can be dangerous without the right goggles. They are great fun though just keep your expectations low for fit and finish lol.