LIDS is a good extension beyond the normal Linux security. MAC is the bare minimum required for any system to even be considered secure in my opinion. LIDS adds many other neat functionality/architectural changes to Linux as well. Though the purist will note that a LIDS enabled system is no longer Linux or even UN*X-like. (as it is no longer a single level system)

Although I like LIDS and strongly believe it is a step in the right direction... I don't think it is appropriate to use in a live non-dev/research environment. The LIDS development model is too immature for my liking and it's MAC structure too closely based on the original Bell-LaPadula model which has a lot of issues. I think the DBAC based Pitbull LX or the Flask based SE Linux as a distant second would be better choices... the jury is still out on HP's Trusted Linux, but it looks promising. They offer simpler to administer security, with a more clearly defined objective (greater design assurance) and more mature development models. (still greater assurance)

just my two bits

catch

d'oh forgot to add links:
http://argus-systems.com/product/overview/lx/
http://www.nsa.gov/selinux/
http://www.hpl.hp.com/research/papers/trustedlinux.html