Good choices.
I'd never buy the expensive cannons, or pay full price for the Snow Job. Hunt around for a good price. I got the Kärcher FJ6 and Snow Job on special and/or price match by SuperCheap Auto. You can usually pick up a good second hand Kärcher on gumtree quite reasonably. IMHO money well spent.
I used to think a good fast ordinary hose was good, until I started pressure washing. Using the high pressure to get rid of all the large dirt/bugs, etc is essential. Something the hose just can't do... and if you try you end up with a swimming pools worth of water running down the road - which is big $$$ these days!
IMHO, you don't need to do the snow job if you're careful with a 2 bucket wash, as long as you pressure wash to dislodge all the bits of dirt and grime you might unintentionally grind into the paintwork.
Good luck!