I can't say that another plane will replicate the performance of the H9 Sbach, but it's not like you have 500 hours on one and lost it and are now looking to get the same characteristics you had before. You just need a good IMAC plane in the 20cc size. Truthfully, you'll do fine with most any Yak 54, Extra 300, Giles 202, Edge 540, AJ Slick, etc. The round cowl of a Yak is better for doing an inverted engine installation, and some say it gives you a little more side area to work with in your knife edge flying. But there's a good reason why these planes are so ubiquitous in IMAC and why none of them dominates- they are all good performers.