Scooterotica

I hope I'm posting this in the correct place.
I have an early Li150s and understand the early models had a weak 3rd gear. My question is has anyone experienced one of these failing and how common is this under normal riding? I don't plan to tune this engine or rag it about. So I'm hoping easy riding would see me Ok with the original gearbox.
Any advice, modifications or precautions I should take I'd appreciate it.
Thanks in advance

I have one on the shelf. I tore the absolute Rs out of it for 10 years and NEVER had a problem. I have NEVERY met anybody who had a problem.
Mine is circa 1964.
I only changed it because I wanted SX200 gearing.

Thanks Chris. Sounds positive. Mine is an early 64, from the frame number I would estimate it at Feb 64 production. I believe they changed the gear July 64.
Only time will tell but its done 50+ years on it (Will check it over when I take the case side case off)