I have never used or even seena Vortex scope but I do see a lot of advertising for them in the recent past. Pentax however has been aroung for quite awhile now.
My only experience myself is with thier cheapest model which is the Gameseeker line and so far it has turned out to be a great scope for me. Sharp and clear with no problems whatsoever. It's only mounted on a .17Hmr though so recoil is not a factor.
A friend of mine has owned a couple of the Lightseeker models that he has used for many years now and absolutely loves them.
I have one Pentax scope a Whitetails Unlimited in 1.5 -5. It's a good clear scope and had held up fine thus far to the .350 RM it's mounted on. I don't regret buying it, but will say I prefer to purchase Leupold, Zeiss or similar when I can due to known quality and excellent warranties found there.
Pentax has been around quite awhile although i have never ever seen a commercial about them. I own both Pentax and Vortex and they are both good scopes.
The pentax is a 3x9x42 lightseeker,it's likely 10 yrs old now. I knocked the crosshairs loose when it was mounted on my 338win mag, customer service was EXCELLENT to say the least...N/C shipping, fixing and returned @ N/C.
The Vortex is a Viper 6.5x20x50PA i have it on my 700SPS varmint rifle in 243win, will likely never have a problem from recoil. The only thing i find with the two scopes is the reticle is thicker than i like. I wish that both companies would make a FINE duplex .
I don't think you would be disappointed with either brand:: I also have a Leupold VXIII 6.5x20x50AO and the Vortex and Pentax are every bit as clear. If you are considering a new scope have you looked at Scorpion ? They have an etched glass reticle, i have friends that use them and they claim that the scopes are an excellent scope for the price, but i have never looked through one.
I doubt you'd be disappointed with either also. I got my first scope in about 1968 in Germany. It was a Tasco and it worked. All I could say for it. About 1970 I got my first Redfield and was a Redfield fan ever since, well until they left Denver. The period between then and now that Leupold is making them, I had no devotion to any brand scope. I found that scopes under $100 tended to be junk with the single exception of a Tasco World Class, I may have got lucky. Bushnell's I got worked very well. My 25-06 wears a 3-9x Banner thats awful old and still working great. Nikon makes a nice scope, I have two. A good scope I'm know and I'm a sucker for Nikon cameras but I doubt I'll get another Nikon scope. Great warenty but customer service so far below Leupold I couldn't believe it. I think Pentax and Vortex are probably good scopes, I hear lots of good things about them. But I am a pretty product loyal guy and now with the new Leupold/Redfield, I suspect that may be all I ever buy again. Is the new Redfield as good as the old Denver ones, I still have two of them. I believe they better be as Leupold is staking their reputation on it.
If I were not so pig headed would I try a Pentax or a Vortex? Certainly! Shoot I tried Tasco's and Bushnells, oh and one really sorry Weaver!
Understanding wind currents and thermals in hilly, broken terrain can often be incredibly frustrating. I've found that collecting and storing milkweed seed pods during the late summer has made me a better hunter in the bluff country that I hunt. These little feather like seed dispersers will float on the lightest of air currents and will show you what the wind is not only doing right at you're location but more importantly down range. I like to use the off season to float them...