Whilst high end LRP stuff is great, I'd avoid the AI and Eraser combo. The Eraser motors don't seem to last long, and the AI speed controller has an annoying habit of getting forwards and reverse mixed up!
The
Fusion Exceed 10.5t system is cheaper, the motor is better and the esc doesn't get amnesia, so I'd suggest that instead.
However I should point out that, whilst both systems are good for a beginner, neither has much upgrade potential beyond the 10.5t it comes with. You will most likely soon find an unboosted 10.5t a bit slow, especially outdoors. At this point there are two ways to speed up the car - run a timing boost esc (neither of those esc's have this feature) which is what I do, or run a lower wind motor (which those esc's can't cope with) like most people do.
The big plus side of the B4 series is at virtually everyone has owned one at some point. That means you can ask pretty much anyone trackside for help. Lots of people still run them, or run B4 based X6's or C4.1's so the chances are someone will have spares. And whilst the rear motor B4 is getting old, the mid motor conversions (X6, C4.1 and Vega) are the most competitive 2wds on the track, so when you outgrow the standard B4.1, just convert.