Has any one experience of rail replacement buses in Germany?

I have an itinerary for Berlin to Prague on 17th March.
I’ve just received an email saying my train is cancelled and telling me to use an alternative itinerary.
It appears to contain a rail replacement bus between Dresden and Usti nad Labem on the new itinerary.
Is this likely to be a pleasant option?
My travel plans are flexible and I could change my plans completely.

(The irony being I’m driving rail replacement for 2 weeks out of Plymouth)

 
Variable ... which is probably not very much help to you.

If you have all day for ... Berlin, Cottbus, Goerlitz, Zittau, Liberec, Prague.   With a steam train side trip at Zittau.   Other alternatives too. The line from Dresden is beautiful, mind - not sure about the road.   

 
We had a rail replacement bus I think between Rastatt and Baden-Baden a coupe of summers ago when the Rhine mainline was blockaded.

Not well done at all - no signage, no staff to supervise, no barriers to ensure orderly queuing and not enough busses. Whole ICE decanted into the street outside the station and became a scrum for the bus, all in 40-degree heat.

Compared very poorly to XC doing similar at Worcestershire Parkway which was extremely well organised and done.   

 
Thank you both. Neither of you have given me confidence!

There appears to be a couple of journeys that don’t involve the bus. I have screenshot a couple of these itineraries, would either of you be able to advise further.

It’s my first long distance Europe trip and I’m starting to get a little nervous. Thanks

 
I suspect that the line is single due to engineering at the moment, the number of trains through cut right down, and many trains replaced by buses.    I'm sure it's more your worrying than any actual problem; it will be very much like UK rail replacement, though finding the bus, and understanding what's happening, can be harder in a different language.

If it were me, that day, I would either take the route I've already suggested - or I would go via Rumburk - a pleasant little town.    I might also see if I could find member UstiImmigrunt who lives along the way.   So - Berlin - Dresden - Bad Schandau - Rumburk - Decin - Prague; the diversion off the normal way, by local trains , is Bad Schandau - Rumburk - Decin, most of which I have done - and enjoyed.

Can't give you total re-assurance, but you have two rail-only options from me now, both which are fun days.