Tabac's scent... You either like it or you don't. I like it. The Tabac aftershave is the same scent, but STRONG.
Arko, to me, smells like lemon Pez candy. And a bit like industrial lemon-scented cleaner. I have no issues with Arko's scent.
Performance wise? Tabac is the gold standard for a great shaving soap. It IS the bar that others try to match. Arko is surprisingly good for its inexpensive cost. It is not as good as Tabac.
For you, Tabac might be the "gold standard" that sets the bar to which others aspire. Four years ago, I would have agreed with you that Tabac performed as well as the best soaps in my collection. But artisan soapmakers have worked hard at trying to improve the performance of their soaps of the past four years. I have made it my goal over that time to acquire the very best soaps available. I now have thirty soap bases in my collection that I consider to be superior to Tabac. Some of those bases are no longer available as the soapmakers have phased them out in favor of even better products. Specifically, these new soaps are easier to load, have better residual slickness, and better post shave moisturizing/conditioning than Tabac.
Tabac is still an excellent soap, but I certainly would not consider it to be the "gold standard" in performance, not anymore. However, I readily admit that the soaps that perform better than Tabac all cost more than the price of a Tabac refill puck. Thus, for those on a budget, Tabac is still a great value.