You're not hearing the argument. In non-OSAS you are most certainly saved and born again and have eternal life when you believe. You have the promise now. The point is, you must continue to believe in order to continue to possess the salvation you most surely have as a result of that believing.
I am hearing the argument. I don't think you're understanding my point of view.
Let me rephrase it:
If you have to "continually believe". How are you a new creation? You don't fully possess it. You are still trying to fully possess it by believing until you "die".
If you have to "continually believe". The focus is on you. It's not on the goodness of God that continually leads you to Him. It's not on the Spirit who is your Teacher. And it's not on the finished work of the cross. Part of "believing" is believing that God will save you to the end. And because you are a new creation, you also have permission to believe you will do good works out of who you are in Christ.
If you have to "continually believe". You are waiting till the end of your life to fully receive "eternal life". You haven't "yet" passed from death to life, but you're hoping you will. You can't have faith for something you don't believe you possess in the Spirit. Part of faith is believing God is a "Rewarder" for those who seek Him. Are you believing God for the reward of giving you a gift that you'll receive if you continually believe, but if you don't you won't?
Furthermore, let me just ask you this. Does your theology help people follow the Spirit of God? Do you follow Him? Do you talk to Him, listen to Him, and trust Him? Do you believe you are fully and completely loved? Does He give you revelation when you read His Scripture and bring the page to life for you? Do you identify more with who you in the Spirit or in the flesh? If it's working for you, then by all means, continue on. But if not, just know there is another side.
If you're afraid to believe you might be "eternally saved" because why then would you continue in good works, then I wonder if you truly know how good God is. And if you're not afraid you won't continue in good works, why be afraid others won't continue in good works as well?