If I'd had to choose one to fight against Vaporeons, it would be #4 for these reasons:
1. Only one w/ solar beam
2. it got high HP, so can last vs Vaporeons
3. It also got low CP, which may be good if you're trying to prestige.
Also, if your main concern is training, I found I can easily defeat far higher CP Vaporeons w/ my Eggies, i.e. say killing a 2500 Vaporeon w/ my 1900 Egg.