Dreadnoughts with Plasma Cannons

[Ming]

I use a FW Contemptor Mortis alot of the time (2xkheres assault cannon arms).  Our FLGS gaming group has no problem with FW models, so long as you also own the rules for them.  The Mortis is good fun, seems costed about right, and has a weakness any brave opponent can overcome. 

 

I also have a Venerable with the PC, DCCW, and Flamer, usually with a drop pod.  If you can get him dropped right, it can be a serious threat to an opponent.  For the points, you could compare that with a 5-man Sternguard sui-pod squad with combiplas or combimeltas.  Sometimes it works great and lives through the game, and sometimes does not last the turn it arrives.  For the points, I don't use regular dreads.

 

The use of dreads all boils down to play style and your local meta.