This is one of my favorite preps to use. Along with conjure flame and then dual shot, I can frequently hit for over 100dmg, especially on those "soft" targets like mesmers and necros...
I use it in PvE... quite a lot actually. I'll approach a group of enemies, hit kindle arrows, then duel shot and rack up 4 hits of about -20 damage each. Its a good spell. Quick to cast to.
Note that it applies elemental damage. Winter could change this to cold damage, which is usually a bad thing if you're aiming for fire damage, but Winter + Kindle Arrows is a VERY good combo in Hell's Precipice where almost every enemy is weak against cold damage.
Ignite is better
not necessarily. Kindle has more damage. Ignite has less, but splash. In PvP, I usually prefer Kindle, because smart PC's don't always stick together as nicely as NPC's do.
I don't think Ignite is a good PvE skill anymore. It triggers the AoE AI routine, which seems to then cause all the affected enemies to re-evaluate their target selection and make them rush the squishies.