My personal opinion is the Wrecker and the Grease Monkey will have more backend than the Venom Shock (purple) but the VS will be stronger.
If the ball is the Venom Toxin (green) then again, the Wrecker and the Grease Monkey will have more backend, but I feel the VT will be a tiny bit weaker overall.
In order of strength, this is how I see them:
1. Venom Shock
2. Grease Monkey
3. Wrecker
4. Venom Toxin
In order of backend skid/snap:
1. Wrecker
2. Grease Monkey
3. Venom Shock
4. Venom Toxin
If he likes the VS already, then my suggestion is to get used to throwing the ball better before committing to a new ball. Use the used ball for a bit longer to develop consistency, that way the new ball can be drilled for the way he really throws the ball instead of how he throws it now.
If shipping back to Honolulu is the issue, then perhaps he should decide when he gets there and match his style with the conditions he sees there.