since you are just starting I wouldn't go with a really high strung horse. I can't really tell conformation wise from the picture..I would probably go with whoever is more laid back (for now), you can always move up to a high strung horse. My mare is and she can be a handful for me sometimes and I've been doing running for years. It can also get pretty annoying if they get really hot..but, If you are wanting to start the high strung horse and you are comfortable with her being hot then I would think that would be okay too as long as you take it SLOW and have a nice trainer working with you..In my experience with hot horses (all of mine have been) the more you push them and train them the hotter they get..
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