I've seriously considered all 4 cars. Even with Satellite & Alarm, you can't get a TCH above about $32k....not sure how you got to $34k. At $34k, I think the TL is quite a competitor. Great car. I actually found it to be too fake--trying too hard to be a BMW with cheaper materials, poorer (FWD) handling; and too loud--actually louder than the TCH on a freeway. But it is a real competitor to the TCH if you fully-load each. Neither the IS250 nor the '06 325i are in the same price range. If you equip the 325i with the basic stuff you'd be up to about $38k and, frankly, when I configure it with the stuff I'd want, I'm up to $41k. The IS 250 isn't as bad, but close.

Lastly, the IS250 doesn't have a back seat, just a shelf with some room for babies in the back--you could never fit a real person back there. The 325i is larger, you can fit a person, but you wouldn't want to for long. (The TL is just fine for this purpose.)

I'm 34 but was considering some of the same cars. Do what you want, if you can afford it.