Permanent Aquascape?

[Madmak]

I'm working on dry aquascaping a new tank with Marco rock and wondering the pros and cons of making the majority of it rather permanent. I would be siliconing the Marco rock in solid as the base rock.

I've always had the best luck with tanks that I keep my hands out of and this would help with that.

Any suggestions are welcome, just want to make sure I have thought of all the details.