I recently finished painting a Laser Destroyer for my Heresy Imperial Fists force. Taking inspiration from the background I wanted to make a footslogging infantry heavy army, but it still needed some solid anti-tank for backup. That and a Vindicator is pretty much the most Imperial Fisty tank there is!
It helps that the thing is a monster on the tabletop too. Running in it's overcharged mode it fires 3 BS4 twin-linked S9 AP1 Ordnance shots (so they re-roll hits and armour penetration and then add 2 to the vehicle damage chart!). It's about the only thing that will have an Imperial Knight shaking in it's giant metal boots!
Painting wise it was the first vehicle that I've ever done with a white undercoat which was a bit labour intensive, but there's just something impressive about bright colours on the tabletop.