You might want to take a look at the Brillelli 26cc SS.
http://www.scottellingson.com/brillelli_012.htm
By the time you but the EVO 26 cc for about $399.00 and a muffler for another $60.00 you can get a Brillelli 26cc SS that comes with EI and a side dump muffler for only $285.00. The Brillelli 26cc weighs in at 42oz and the EVO 26cc weighs 33.6 with out a muffler. With the muffler the EVO 26cc out weighs the Brillelli 26cc. The EVO is rated on top end at 9000 rpm, the Brillelli 26cc 10000 rpm. Might be worth looking at. I run the Brillelli 26cc SS in a GSP Giles 202 swinging an APC 17X6 prop at 9300 rpm right out of the box.