Mods I'm getting, need opinions on the later parts...
 

Got these parts to install soon here. Stock 2008 EVO X GSR, 40k miles.

Buschur InterCooler
Buschur Upper Pipe
Migen Exhaust
Test Pipe
O2 Dump Pipe
Grimspeed 3-Port
Walbro HP255 Fuel Pump
AEM Intake

Do I need the following :)

ID1000cc Injectors
GSC S2 Camshafts
GSC Beehive Springs and Titanium Retainers
APR Headstuds

Lastly a tune after some break in. I have no aim really. I'm sure I will be fine with the HP gain from the first list already as I'm much older now and drive very conservative unless I head up to the mountains. But that doesn't require power :) Anyways, I'm concern about the health of my engine with the parts on the second list. Secondly, the price is substantial as well and will I see a big gain from them in HP.

Lastly, any other parts that I may be missing from either list that is important? For example, coupled with the other parts would providing a big boost in HP. At this stage I think I'm just going to get them but wanted to make a last effort to get opinions on this. Maybe some of you can convince me otherwise :)

I am expecting at leastd 450 from this setup if not more with a good tune. Opinions on this as wel? Thanks in advance from a long time lurker.

You have a 2008 Evo? What type of break in are we talking about? I don't think you will see 450hp though.

450whp? If so you'll definitely need a larger turbo. I would skip the cams and upgrade the turbo instead; it will yield much larger gains for the money. Something along the lines of an EF3 or FP Red should be enough to hit your goal. Or if your budget allows it get a new turbo and cams

The turbo will be the next step but we'll have to see. All the prep is for a larger turbo though.

The break-in was for the camshafts when they are installed. Couple of minutes of driving.