I've flown with the Micro Air transceiver and transponder combo. for over 8 years now with no major concerns other than their intercom on the transceiver and my first transponder was bad so I had to return it to Australia for a replacement. 2nd transponder works OK but sometimes I think it's a little under powered.
I'm able to communicate with towers and air to air with decent clarity and range with the transceiver. Size, weight and price were main factors in original purchase. Micro Air's intercom was less than ideal so I've always used a separate intercom. So much for saving weight, panel space and complexity.
Today I would be considering an MGL V-6.
MGL's radios look to be smaller than the Micro Air yet transmit at a very respectable 6.5 watts of power.
The VHF-6 from MGL looks to be feature rich like the earlier V-10 but has a stereo intercom. It is a fully digital traditional VOX intercom system but also incorporates their proprietary VOGAD digital intercom system. It also has the 8.33KHz frequency tuning capability.
If you overlooked MGL's offerings in compact yet capable aircraft transceivers you might do just a little more investigating. MGL may just be the perfect fit for your Kitfox. I know I'd like to try one.
Now if we can get them to do a transponder.
Questions?- Contact MGL:http://www.mglavionics.com/html/contact_us.html