it wud be a losi eight 2.0 rtr buggy that id suggest if he wants to enter racing ..
it comes with a nice radio by spektrum , a engine starter box, n the engine is powerful enuff to start off ..
i won my first buggy raCe with it in beginners category without a single upgrade .. box stock set .. but its little expensive at about 600-650 usd
or
if u cud wait a little u can get the hpi d8s rtr which is cheaper than losi but promises to b gud as losi rtr minus the spktrum radio n staRTer box .. u get a 2.4ghz hpi radio and a pull start engine
this car too is a race worthy one
both are very proven platforms
and u cud get smthng like ofna hyper7 or hongnorjammin x1 rtr if only for bashing
but first ask your brother if he plans to race or bash
EDIT-- sorry i cudnt think of ultra lx2 before .. dats a very good buggy as well .. add ultra lx2 as an option ..