[200q20v] successful r134a conversion on 86+ a/c?

[Chris Covington]

Has anyone done this using the stock hoses?  I hear there is a possibility
that any of the new, smaller-molecule refrigerants can leak through old
hoses, the result being that the car will hold charge for about a month or
two then deplete.
Has anyone used R134a successfully on a Nippondenso system for a long
period of time?

Chris
'91 200q20v

ps - If so, then there won't be any issues with Autofrost leaking either