Please help with the reasoning, client wants to switch to .NET
docs.google.com
docs.google.com
I quote them a price 33% higher.
Never once despite the most insistent argument that it just had to be done the new way has this ever failed(1). "Oh, you mean is costs more?! Never mind then...", is the usually response. Once, I had a client go with someone else who promised what they asked. I heard later that it was quite a disaster.
(1) I've had a guy tell me that using a certain technology was a matter of national security and then change his mind to save $1500.
So if I were to go to that same individual with this tactic they'd jump on it. Scary, but true.
If you have good reasons for not wanting to go with .NET, you have no need to be asking us for reasons.
If, on the other hand, you don't have good reasons, then what's the point?
> The biggest advantage that outweighs them all, do you and your team have more experience in the Java stack or the .NET stack. Push harder for that stack because it will be cheaper for the client if you don’t have to learn a new stack. <- is your company / team capable of writing .NET software today, or would a reschooling be in order ?
To which the OP replied:
> exactly, but its not good enough for the client
So the OP is looking for reasons, and the OP isn't best qualified to offer reasons not to use .NET because of lack of familiarity with .NET. This is why the OP is asking here for information to support his decision rather than information to make his decision.
Back to the original question, why are you trying to build a CMS from scratch? The project sounds like a customer facing marketing site. Is it giant brochure (web site), or does it actually do something (web app)? If it's a giant brochure and the client just needs to edit some pictures here and there, there are plenty of CMSes available on the market for Java and .NET. My company recently switched to WordPress for our marketing site because we realised we were wasting too much time reinventing the wheel in .NET for a mostly static marketing site.
Now, if it's a web app, I would recommend going with whatever technology that talks to their back end the easiest, which in this case, sounds like the client is already using Java. I wouldn't want to try to get Mono to work on Linux, or switch to Windows hardware just to run a .NET web app, although I much prefer C# over Java.
If this is one of those anti-Microsoft zealotry things, then I'm really disappointed. Their tool chain may be proprietary, but with things like NuGet and .NET MVC spawning from inside the belly of the beast, I can't vilify them one bit.