Penta vs Tonkor, Discuss

So I've been seeing so many "OMG Tonkor is OP" posts that I decided it's time to get into the grenade launcher action myself. I built both the Penta and the Tonkor, and so far I'm honestly finding the Penta to be much better, despite being a Forma hog. I like the fact that I can auto-detonate the grenades vs with the Tonkor I have to wait until someone runs into the grenade.

Is there any reason the Tonkor is better (Forma and magazine size aside)?