1) It is true that there are indoor tracks that run nitros. We used to have one locally that was really nice. There is an indoor-only track for electric onroads, but it is only like 40x40ft.

2) I didnt want to get into it much, but that Baja setup is going to be ridiculously expensive. The batter(ies) alone would cost $500 minimum for only a few minutes of runtime at 8HP. That is using two 5s 4000mAh packs. A Single 10s 5000mAh pack like that page recommends is probably $750.

3) Its very true that you almost can't competitively run an RTR electric unless you are running in a stock class, in which case you wont have nitro-matching performance and this argument is pointless.

4) The argument about which is better is like the age-old argument of Automatic vs Standard transmissions. If all you want to do is get the numbers, then the automatic is for you. If you want to get more out of it than that, then get a standard. Auto- and Standard-loving guys almost never see eye-to-eye, since they obviously have different PERSONAL preferences that can't be legitimately argued.