Oklahoma Aviation (flying out of Wiley Post) has a great airplane and Bret Wyatt is a decent instructor. It is expensive training though since the 2011 Baron G58 rents at $775/hr wet. The gal at TCC (Tulsa Community College, flying out of R.L. Jones), as mentioned above, is also good. I don’t remember the pricing there. For the OK area, do your practical in Wichita Falls, TX with James McElvain. No reason to use any other DPE.