You may be unpleasantly surprised. I have TWSBI Eco-T pens in both <M> and <F>, which write similarly to some Japanese <B> and <M> nibs respectively. I would recommend, if you want something with true portion control, to get a Pilot Prera in <F> or a Kakuno in <EF> (or any pen with a Japanese nib), just to check it out. Both are fairly affordable.

Also, given you’re a lefty, you may want to avoid “good paper” for fountain pens. Coatings on the paper that allow inks to “sit on top” of the page while they dry, preventing feathering and allowing the ink’s properties to develop, understandably slow the drying process. In addition, avoid Noodler’s inks. They look beautiful but dry at an absolutely glacial pace—in my experience, up to several days’ time to fully dry (unassisted, in a dry environment) on Midori MD notebook paper.