Which car would be better. I have been researching for future purchase. The RSX about 3K more than Civic Si, but it seems the Civic brings more to the table...LSD (RSX does not have this), only 4 less hp (not sure on torque. I would favor the body style of RSX.

Your thoughts..........  

If your looking for a daily driver than either one, RSX maybe. If your looking for a race car, keep looking.

K20A stock bottom ends r weak as [censored]. RSX forums claim that they can only run 6-10psi on turbo kits, before things start getting iffy.
Might I suggest any of these cars as an alternate to the 2 hondas you listed. This only applies if your trying to be fast.
3rd gen RX7
SRT4
EVO8
WRX STI
GSX Eclipse
MR2 Turbo

Any of the above turbo cars are capable of 20mpg around town, and sub 12 second quarters as daily drivers. All of them were built for boost, so you wont have to touch the internals anytime soon, unlike, if you boosted an RSX or Civic Si. Not to mention those Hondas are torqueless and only take it in the top, turbo motors are much more torquey.

Generally turbo cars are a lot cheaper on a hp to dollar or ET to dollar scale. LSD's arent as essential to getting good launches like they are on FWD cars like the civic. When you accelerate the weight of the car pulls back, putting the weight on the drive tires, where on FWD cars it pulls weight off the drive tires, making for crappy 60ft times. SRT4's overcome this FWD problem by having a large boosted 4cylinder with a 16g and monster IC from the factory. Some came with LSD's.

My motor can handle over 25psi of boost, or 450whp on stock internals. On honda's, you have to spend thousands on strengthening the block on there motors, just to match what my stock 3sgte is capable of from the factory. I would suggest getting a car built to perform from the factory, rather than build it up to be fast.

Would you rather run 14s or 13s with the hondas (good luck getting a fwd car to break out of the 13's on street tires), or 12's or 11's with a turbo car?  

The K20Z3 motor is iron sleeved which makes it stronger than the RSX.  LSD on it gives great launches with my experience driving it( I own an 07 Si).  

As for boost supercharging is a lot safer for a K series motor because you cant mess with boost settings so you dont have to worry about feeling iffy unless youre going to run a marathon road race, which companies have done quite successfully with 8th gen civic Si's.

I will say it lacks torque from the factory but Hondata ECU reflash cures that and resets vtec actuation lower and redlines all the way to 8600rpms.  Thats the one thing that the Si really has going for it.  You wont find many non exotic cars that rev as high as it does.  

For an occaisional track driven, daily driven, street car the 06+ Si is in my opinion by far the best car you can look into if you are looking into an naturally aspirated FWD car that can keep up with some meaner cars for not much money at all.  Not a great set up for an all out race car, but way more reliable/cheaper to maintain/better gas mileage than any factory forced induction car worthy of mention.  

I'm getting ready to get my first car and its going to be daily driven but i want to be able to keep up with the big boys in drift comps. What would be a good car to start with...other than an AE86 cause i can't find one.  

^ if your getting your first car don't get into drifting unless your willing to spend lots of money on body parts that get ruined when you crash it.  start out with learning basic high speed car control, and how to correct oversteer when your car breaks loose through a corner, then you can safely start learning how to force oversteer and hold slides through entire laps around a track.  240sx is a great inexpensive car for drifting, and with an SR20DET swap with bolt ons it can be pretty fast as well.