I'd second Jay's recommendation on Jet Air. We've dealt with the
Galesburg guys and they've always been outstanding, whether it was
engine, avionics, or airframe issues.
They are a Cessna Single and Multi-Engine Service Center. I've seen
several twin Cessnas in their shop when we've had our 172 up there.

Galesburg - Contact Jim Ortery, Shop Manager (888) 253 8247
Iowa City - Contact Klay Johnson, Shop Manager (866) 453 8247
http://jetairinc.com

Brock Boss
Student Pilot/Co-Owner
N3916R

O. Sami Saydjari wrote:
I am looking for recommendations of good Cessna 421 Shops in the
vicinity of Wisconsin (within a 300 nm radius od KISW would be nice).
Does anyone have any positive experiences to share? By "421 shop", I
mean a shop that has significant experience maintaining 421's and
preferably one where someone at the shop is qualified to test fly it
after maintenance.

-Sami Saydjari
Cessna 421C
N5554G