I believe Tactical will be coming out with a sump plate for the LR3/4 eventually, but probably not going to happen just yet. Last time I was there to get the rock sliders fitted on my LR4, they did take a good look at the front end and they did have a Mantec OEM plate for the LR3 in their shop for "inspiration", so it's in the works I am sure. Their LR4 sliders should be ready (including the all-important bracket to lift the AMK compressor of late build MY2012 and newer up and out of the way.)
I also went with Asfir for the sump guard, it is indeed a nice chunk of aluminum and fits the LR4 well, although if you are picky you can tell it was originally designed for the LR3 and "adapted" to the LR4, the front end of the plate could be a few inches wider and squarer to fill the lower bumper of the LR4 better (for about 400 bucks though, no complaints here.) It's just as strong than the $900+ OEM alternative and it also extends further under the vehicle, protecting more stuff than the Land Rover / Mantec offering. I had it powder coated black - gotta keep the black pack thing going...
I don't have a winch.
The good thing about the LR4 is you can change oil and filter from the top of the engine. I wouldn't look forward to removing that guard every time an oil change is due.