There are no stability problem.
I have a few webservers 100% in go that run for months, serving about a million queries per month without any problem (mostly json, through GET, POST, and websockets).
They're on 64 bits ubuntu servers but I guess you would have difficulties producing the so much gossiped about 32 bits bug, especially with a web server.
Don't use a front-end if you have no specific reason : It's easy to make a complete web application just using Go.
You will be far from alone. In my opinion Go is especially well suited to build long running servers. Goroutines and channels makes it really easy to handle both user requests and long term tasks (or, for example, do the postreatment of user queries after you answered the http query, which isn't so easy in php and is too many LOC in java if you want to do it properly).