I would recommend against both. The PZ P-51 (perfectly sutied to outdoor flying by the way) is a 3 channel. It has no rudder. You may not fly knife edge or hammerheads and not need one but at least you should know it isn't there. While there are some good models from Nitro Planes there is also a lot of junk. Personally, I wouldn't risk my money there. I'm not familiar with the one you mention but there are so many great models available, I just wouldn't go there.
My suggestion? PZ T-28. Full 4 channel, fully aerobatic capable, some wing dihedral for self correction, easy to fly, responsive. Easily one of the bests flying models I've ever owned. I like to post images so here's my T-28
