it really depends what you intend to do, and how the individual items will function in the given WoW Classic Client…
Arcanite Champion
Binds when equipped
Two-Hand Sword
129 - 194 Damage Speed 3.00
(53.83 damage per second)
Durability 100 / 100
Requires Level 58
Chance on hit: [Heal self for 270 to 450 and Increases Strength by 120 for 30 sec.]
Arcanite Reaper
Binds when equipped
Two-hand Axe
153 - 256 Damage Speed 3.80
(53.8 damage per second)
+13 Stamina
Durability 100 / 100
Requires Level 58
Equip: [+62 Attack Power.]
Both weapons are very powerful in their own way, but each is individually catered to its own specific function, and the extent of this function will be a result of the scripting which defines it.
this mainly being… Should Arcanite Champion possess an ICD (internal cooldown) it would vastly weaken or strengthen the effectiveness of said weapon due to it being able or not to proc off multiple reckoning attacks simultaneously, however assuming that it does not have an ICD…
that would yield 5 attacks multiplied by a maximum of 450 healing offering a total of 2,250 healing to the player based off one attack combo… and then on top of this, should it proc off of every SoR proc as well this would jump it to a total of 4,500 healing on one attack (in a best case scenario) … making this an incredible PvP weapon (and this doesn’t account for the potential of +healing interaction however it is highly likely this will not be a factor.)
that being said if it does possess an ICD that reduces that grand total back down to a total of 450 healing (in a best case scenario) no matter the amount of attacks made, and as a result it wouldn’t be nearly as effective…
While examining Arcanite Reaper however; we can see that this weapon offers a vastly slower attack speed and simultaneously a far higher top end, to this end it becomes apparent that Arcanite Reaper would be the far superior PvE option of the two especially in regards to utilising a SoComm rotation, and should Arcanite Champion possess an ICD; Arcanite Reaper would also be the far stronger PvP option… that being said should Arcanite Champion not possess an ICD this could very much be up for debate, haha I mean who wouldnt love 4,500 healing at the swing of a sword.
At the end of the day it all comes down to preference, play-style and taste however; and whatever makes the game the most fun for you.