How much of a risk is 5.x ... ?

Several here know of the problems that I've found in the past with 4.x, 
several of which, through the patient help of alot of ppl on these lists, 
have been been fixed.  Most of the problems have revolved around the 
unionfs stuff that I use quite heavily.

I'm just about to order in a new server, and with the 5-STABLE branch 
being, more or less, just around the corner, was considering using this 
new server to start migrating to 5.x ...

I run both my desktop, and laptop, on 5.x, and can't say that I've had 
many problems with it ... but I also don't demand near as much out of 
those two then I do with the servers themselves.

Depending on availability of the hardware itself, I'm looking at end of 
June, earliest, to get the server online ... and was figuring a slow 
migration of VMs from the 4.x server -> 5.x, to slowly build up the load, 
as well as to inconvience as few as possible if it crashes, and needs to 
be debugged.

So, I think the question more or less comes down to whether or not 5.x is 
to the point where I could be as confident with it as I am with 4-STABLE? 
Like, I believe that most of the fixes that David and Tor put into 4.x for 
the unionfs stuff were migrated up to 5.x (or vice versa), but I also know 
that there are several things I can't do with it under 4.x, nor expect to 
be able to under 5.x ... but should I expect 5.x's unionfs to be in about 
the same stable as 4.x?  Or in a worse state?

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Marc G. Fournier           Hub.Org Networking Services (http://www.hub.org)
Email: scrappy_at_hub.org           Yahoo!: yscrappy              ICQ: 7615664