yeah the hyper 8 seems good for the money must be better than the hyper 7 i would go with the hyper 7 but sinse the hyper 8 come out stick with that.
i run an x-ray xb8 but there is now an x-ray xb8 tq out which is most offen then not always compared with the mp 777 sp2's so if you want real high performance and are prepared to pay abit extra go with the xb8 or 777 but money wise go with the hyper 8 they seem good performance and good bang for the buck. go for the pro version. thats just my opinion so go with what you want.
but if you scope around you could pick up a good second hand 777 or xb8 for a good price (cheaper than a new hyper 8) and have the best of both worlds.
i bought mine second hand 2 months old and was hardly scuffed so im happy for what i payed and usually second hand cars have the engine and evrything in them just a matter of finding a good deal check ebay out.
engine wise have a look at the o.s rg (sports) .21 you cant get any cheaper and they are ment to keep up with the big guns for a fraction of the price.
the rb engines are good and they offer a range of engines or o.s engines.
i ran an sh engine and it was really fast bottom and top end type a search for any of these brand engines and have a peak of what they got to offer.
if in doubt go to your local track and ask what the guys are running there and ask about the different cars because like you they had to make a choice on their car once.
i recomend you check the kyosho inferno mp-7.5 kanai 3 cars they seem to be really good some people prefer them over the newer 777's sp1 and sp2's.
i think it all comes down to the driving part of racing but it doesnt hurt to have a great car behind you does it