Help w/ Recommendations Digitrax/Decoders

Hi,

I currently collect 2 scales. N & Large 1:20.3. For my n scale layout I have switched over to DCC this last year and loving it. I would like to switch my large scale layout over.. I currently have a Digitrax Zephyr with a DT400R throttle.

For my large scale set up, I have a temporary layout using Aristo Steel. I'm currently purchasing Sunset Valley for my perminant layout.

My Engines include all Bachmann:
K-27 w/ QSI aristo sound decoder & programmer software
Consolidation w/ Soundtraxx Sierra
Side Tank Porter
Shay

My questions.

Will I only need a Digitrax DB200+ 8amp Booster to get started on running 2 engines at a time?
I'm sure I will need a DCC meter to determine how many amps each decoder would use. Would you recomemnd one like Tony's DCC reader? Is there a cheaper option?

Since my K-27 is the only engine with a mobile/sound decoder, I will need to purchase decoders for the rest of my engines. I will have to read up if the Sierra has a mobile decoder.

Since I have the QSI programmer, I should stick with using a QSI magnum with my Shay. Is there any known problems with installing that sound decoder with the Shay?

Also any recommendations for a mobile only decoder for the Porter.

The QSI decoder on DC is an obvious pain without a battery, so switching to DCC is a must.


Thank You for your time.

Ralph