grendel083 wrote:You're right, it's not cut-and-dry. Can't really look at them in a vacuum, they're both great options.
The main question is, what's in the rest of your list?
Are you lacking Ap2 weapons?
Are you short of a unit that can hide on a backfield objective and snipe vulnerable characters?
Pretty much this.
The way I look at the Mek Gunz is:
Lobbas are versatile due to their long range and ability to fire indirectly. They are also our only source of Barrage, which can be wildly useful in of itself. While the hits may not be strong, you can tack on a lot of wounds with them, and are an excellent means of backfield pressure.
Kustom Mega Kannonz loos a bit of versatility by not being Barrage, but they are a heavy dose of S8 AP2. While Lobbas may really only be ideal for light infantry,
KMK can hammer pretty much ANYTHING that your opponent fields. Infantry get roasted, vehicles can get popped,
MC will do what they can to stay out of sight from them. They are far more intimidating...but a little less sneaky.
Both provide durable objective holders as well.
It really depends on what you plan on facing.