You won't dictate fights very well with a melee army with 18" guns. Having run that with my orks for several months its rare to dictate the initial charges.
Other bike armies hurt you because they can shoot you pretty well outside your charge distance, but you can't do the same.
Also relying on HoW is... iffy. 4d6 str 6 rending hits sounds amazing and it is when it works, but getting those off is a lot more difficult then it sounds. If you keep the caltrops in the front they get shot to death, but if you put them in the back they probably won't get in Base to Base on the charge. And if you don't get the caltrops off...it won't end well with str 3 attacks and 5+ armor.
Overall I think you will completely wreck non Tau/Eldar Gunlines and just **** on Knights(be very careful of the no jink vs explosions though... **** is gay), but you are going to quite literally auto-lose to Tau simply to smart missiles everywhere, and have a very difficult struggle vs Eldar and other bike armies. Everything else is toss up. You will also get to enjoy the fun that is cleansing flame just like my orks :P