Tikka makes a very good production rifle. IMO, it deserves a good optic.
What distance will you typically be shooting?
Your questions are sort of random, do let me try.
1) MOA or MIL. If you don't know, then go with MIL. More long distance shooters are using MIL and FFP, so this gives you a chance to learn. I started shooting MOA and 2nd Focal Plane. I am one of those odd balls that is ambidextrous in shooting. I can move between MOA and MIL and FFP and SFP. 10 years ago, most shooters were MOA. MOA is perhaps easier to learn if you are bench shooting, as is SFP. But, the discipline and benefits of MIL in achieving distance solutions without a rangefinder and FFP far outweigh the simplicity of MOA. Today, most MOA shooters are hunters, solely range shooters, or Boomers like me who don't want to change. If you have been shooting for 20 years in MOA, then don't change unless you see the need to change. THERE IS NO RIGHT OR WRONG, but the majority of long range shooters are MIL/FFP, so if you are not already a heavy MOA shooter, go that way.
2) Razor v. PST. When you get to scopes, it is hard for anyone in this forum, myself included, to not have a bias. The Razor is a great optic, but there are models that I seem to like a lot, and models I do not. The Razor LPVO versions in 1-6x and 1-10x are outstanding. The longer range 6-36x seems from all accounts to be a winner. The models in the middle do not seem to have the consistent quality. Now, this is a personal observation, and I will get kicked in the ass by 10 members who swear by the 4.5-27x. On the other hand, the PST Gen II (notice I said Gen II), have a great track record, and are priced right. They are not the same optical quality as the Razor, but are good scopes, and priced less.
3) I would not pick a scope with price as my first parameter. Obviously, it counts. There are great S&B and ZCO scopes that will amaze you, at 2x to 3x the price. The Tikka is a B+/A- rifle. It is one of the best production rifles, IMO, available. BUT, it is a production rifle. It is not a custom-made rifle. What does this mean? It means that it will be a fantastic rifle, but not a great rifle. It is an Audi, but not a Porsche.
. People will offer their experience with the Tikka, and I have shot it and we sell it. I am not the best marksman, but I am getting 3/4 to 1/2 MOA on Tikka Tactical .308 and 6.5 CM, while I am consistently getting under 1/2 MOA on several similar Cadex rifles. But, my Savage rifle is getting 1 MOA to 3/4 MOA, so you want to match the scope to the rifle, like a transmission to an engine. If Price were the most important component, I think the Arken would be my first choice. But, I would encourage you to look at the Leupold Mark 5 as well as the Nightforce NX8, as well as the two Vortex models you mentioned. I would not get the PST Gen 1, so take a hard look at the model. I would put the Gen 1 on a lesser rifle. I would put a ZCO or ATACR on a custom rifle.
4) Distance. I asked, as this will influence your selection. 6.5 CM can reach-out beyond 1,000 yards. If that is your goal, then you will want 20x to 27x for sure. If you are shooting 600 to 800 yards, you might select 18x to 20x. The more magnification, the more your scope will be stressed and give you some distortion, unless you are buying a very high-end scope. For example, we are finding some uber-bargains on scopes at the 6x level that are astounding. But the level of quality needed for a 6x scope is much different than at 35x, for example. Going up in magnification is not always a good thing, and you will pay more, even on an average scope.
5) Reticle. You did not mention it, but take a hard look at the reticles. You will be spending a lot of time staring into them. They are many times overlooked, but become important. Nightforce, Schmidt and Bender and Vortex reticles are all very different. And illumination is either important or it is not, and do you want illumination on the entire reticle, or only in the middle.
Hope that helps, don't rush. Picking a scope is fun. This post is not commercial, but if we can help with your decision, happy to chat. On the commercial end, we are dealers for all the brands mentioned, plus more.
