Xtrmbobbyp

I have a s4 with a s5 hot side/bnr stage 2? I have exhaust, fcd, and airfilter. I would like to buy injectors, but wanted to wait until I bought a rtek 2.1 or haltech E8. Just don't know which one to go with. Will go bigger on the turbo in the future ( so I can atleast grow into it), instead of buying something I'll grow out of. I'm also interested in the microtech lt10. Need to more info. before buying something I'll grow to hate. Thanx guys