These are my favorite Mechs and the ones I'm using consistently -
The Anubis, simply and excellent Parallel Mod. I love the way it's designed, the feel and the punch is outstanding. Very easy to maintain and clean
The Piglet, another very well designed Mod. This Series Mod packs one hell of a good punch, well designed and build quality is great.
Also my Arthas Tube Mod, all Copper, hits very well. I like the extra battery life the 26650 gives me and the extra 5 amps is a big plus. The machining is very nice and I really love the smoothness of the fire button, over all an excellent Tube Mod.
Now here is another outstanding tube Mod, the Oros V2, another very well made Mod with and excellent fire button. This throw on it is about as perfect as one can get, I really like the button lock mechanism and just how smooth the button is. This Mod hits very well and really love how well made it is and how comfortable it is in the hand.
I've got over a dozen Mech's and these are my favorites, the only one missing from these are my Mutant 26650 SS Tube Mod. I'm at work today and it's one of the rare occasions I don't have it with me today. It and my Anubis are the two that are pretty much attached to me on a daily basis. I have it paired with a Tank for when I'm mobile and my Anubis paired with an RDA.