I have a limited budget but want to eventually have a Brushless system and LiPo. My question is given that I have two 7.2V 2400 NiCd and two 7.2V 3000 NiMh, and that I longer is the most important to me right now, should I first purchase a Brushless system, or LiPos?

At first I was just thinking about LiPos, but I will eventually want higher voltages, like 3S and 4S provide. Two of those and I'm beyond the EVX2's limit... unless I could get better runtime with only a single high capacity 4S LiPo? (plus the LVC)

Then a friend said that Brushless is more efficient than Brushed motors and should give me longer runtimes (slightly longer) with my existing batterys.

I'm assuming that 2 high capacity 4S LiPos are about the same cost as a HVPro 6.5T (I'm into friendly off-road racing and bashing, not much drag racing). Finally there's my Vision Peak Ultra which can only charge up to 3S LiPo...

So, to people more on this than I, should I get a decent Brushless and use my NiCd and NiMH or 2S (or 3S or 4S) LiPos first?