Aram,
The first shave is always the most tense and tentative one. I am going to have to say that jumping to str8s w/ a Japenese straight might be a bit much to handle. I am assuming that the str8 is shave ready.

You have made a significant investment already. My recommendation would be to get a traditional str8 and begin there if you can.

If not stick with the Tosuke you will get the hang of it I am sure, the learning curve with a Japenese str8 might be a bit steeper.