Slide Ear with Snaffle?

OK, so first off we are in the process of vet checking and purchasing a 5 year old gelding. I have a background in barrel racing and have always ridden my horses in headstalls with a throat latch. This gelding, apparently, can ride in a smooth snaffle or a curb, but the owner had him in a twisted wire snaffle.
I am definately going to start him off in a standard mid-weight O-ring snaffle, but I was rummaging through my old tack and found a REALLY nice double slide ear headstall (no throat latch). Would I be able to ride him in a that with a snaffle?
I admit that I don't have a TON of experience in headstalls and bits, I always just went with what I was familiar with. I know I have seen people riding with slide ears and snaffles but I wanted to make sure it was kosher. I was always told before that you wanted to avoid a slide ear if you had a horse that rubbed on things, which I don't believe he does.
I have no problem in buying a full headstall with throat latch if I need one, I just was hoping not to have to do it right out of the box with him.

I would love to get your opinion as to whether or not the headstall is an OK choice.

ok... so i would really appreciate any help at all. this horse is getting vet checked tomorrow and anyones advice is welcome.

I've never had a problem doing it.