Which Transponder?

Hi All

I am contemplating getting a transponder for our LS3a. It seems the choice
is between either a 175W or 250W Becker "ATC 4401" unit or the Microair
"T2000".

Has anybody had first hand experience with any of the above?

What were your experiences, which unit would you recommend?

Which altitude encoder did you use?

What batteries do you use and how long do they last in flight?

Where did you mount the antenae?

Have you had any operational or reliability problems while flying?

The alternative might be to get hold of an old Terra unit. However these
seem virtually unobtainable, not very reliable and very
difficult/expensive to repair if/when they fail.


Thanks

Ian