There are two paid products that I know of:
DXF Page Exporter - cheap but somewhat poorly implemented with crappy results. Converts everything to polygons - texts and lines included! Real world coordinates export is not precise - seems to be a rough approximation - in their words "data precision loss is due to real-world to pixel coordinate conversion". Objects are exploded into many little parts. Overall the DXF when rendered looks good but the drawing has no engineering value.
SmartExporter.DXF - costs more but much better in terms of usability of the exported drawing. Overall good symbology mapping with some shortcomings here and there.
To be complete - there is a third company called CEDRA but they are outrageously expensive and I haven't been able to make their exporter work for me. It is not easy to obtain a demo version. The exporter seems to be very limited, requiring to follow certain rules when designing your ArcMap documents, layer coordinates do not register in the exported file, the symbology mapping is very basic, the whole process is very manual, layout elements are not supported, grids and north arrows are not exported unless converted to graphics and a lot of other quirks and problems.
In a nutshell - if you want to look at a pretty picture in AutoCAD - go with DXF Page Exporter. If you want to be able to match exact coordinates, edit the exported file and do any other engineering work with the exported document - go with SmartExporter.DXF. If you want to waste your time and money - go with CEDRA.