What to do, E-Revo or Conversion

Two days ago things were so clear for me, and now I'm totally confused. I was prepared to get a Platinum Revo and convert it to Electric. I was planning to use one 4s battery. Now I'm no so sure I want to convert, looking at the E-Revo, there are many things I like, some I don't.

I will narrow my question to the forum to just one issue - batteries. I plan to race this in the PMT class (Production Monster Truck.) For most club races, the main is 10-20 mins long. When I was thinking conversion, I figured I could likely get away with some light(er) 4000-5000mAH batteries and possibly make a pit half way. With the E-Revo using two packs it makes a pit twice as time consuming. That alone is the single biggest reason I'm leaning toward the conversion. What do you guys think?

Anyone out there making a SOLID 20 mins on one pack? What capacity?

DM