yeh, gen3 really wins mostly in stock format. if you already have one it's cheaper to get more power out from compared to a gen2, as you have to upgrade the ecu and turbo to get to the same limit the gen3 can on stock components.
 
then you also running the risk of blowing the stock HG as it's composite not MLS like gen3.
 
but it's not worth spending the money to convert to gen3, money better spent on uprgrading what you have.

^yep gen3 has the 'CT20b' stock...

You already have aftermarket ECU, intercooler, intake piping and ingnition coils, might as well go for a bigger turbo if you want to make more power,
 
That is depending on how much power your looking for.

Best off doing everything aftermarket. You can get bigger injectors than the Gen3 540's, the stock ECU changeover would be non beneficial compared to an aftermarket MAP equipped ECU & CT20B turbos would be second hand & give a small power increase compared to aftermarket.

Turbo upgrade/modifications really depends on your goal for the car. Make it easy on yourself & decide how far you want to go @ the start so you can plan the right modifications without wasting money.
 
Does your turbo/power fall over by 6000rpm? If so, most likely it's an untouched CT26.
 
To be honest, modifying Gen2 3SGTE's puts you in a bit of a dilemma. There's no "cheap" effective modifications & unlike Mitsubishi's, you're forced to change ecu/injectors/fuel pump/turbo to get any meaningful results. Past the usual intake, exhaust, boost controller & cooling modifications, it's quite expensive. If you're committed to the car (like many of us are), then you can do the usual modifications, then change turbo, injectors, fuel rail/pump (E85 would be a great move if you can) once you've accumalated the necessary parts/funds. Rebuilding the motor etc etc can come when necessary.
Another alternative that I recommend to those that don't want to venture far from stock, is to replace the turbo (now or when it dies) with a bolt on replacement turbo, such as the Blitz K1, PE1919T or CT27. Those can still be managed by the factory ecu @ upto about 16psi safely, but bear in mind your injectors will start to hit the ceiling. Coupled to a free flowing exhaust (incl. dump pipe), intake & intercooler (sidemount will suffice in that case with an upgraded fan), it should stay with a similarly equiped Gen3.

Ant1
Well my tacho doesn't work, but yeah it does cut out early. Which on a different subject, how the hell do I get it to work?!?! Lol, I have been told I need to wire something to the alternator or something because of the aftermarket ecu.

Do you know if you still have the stock igniter? Work-arounds are required to make the tacho work without the stock igniter.
This is due to the fact that some 'old' cars, like the SW20, have a tacho that determines the RPM based on the time between each voltage spike on the negative of the ignition coil (which is connected to the tacho wire inside/via the stock igniter). If you don't understand what I mean, don't worry, I used to do stuff like this for a living!

No I don't have a stock igniter.. What do I have to do to get it working?.. It's driving me nuts haha. As well as my speedo going crazy, but I'm going to have a look at that now.

Boost controller (Apexi AVC-R), aftermarket ecu (EMS 8860), aftermarket ignition, side mount intercooler and an aftermarket exhaust.. Pretty sure that's all. Just want it to have a bit more power, nothing to crazy, at the moment I'd rather keep the inside of it stock, but that's not to say for in the future.