Agree with all the above but would add that there's a lot of ground covered in the PA28 designation the 140 is quite a different proposition to the -200/201 and 201T versions (the latter being retracts with wobbly props and what not)
But even in the fixed gear fixed prop versions there's quite a bit of difference (unsurprisingly because of the availible grunt) The 140 climbs more because of the curvature of the Earth whreas the Archer (180hp) is quite a bit more muscular. Never flown a Warrior but I guess it follows that it would fall somewhere between the two in performance.
As has been said before you have to work pretty hard to get yourself into serious trouble in a PA28. And there's a lot of kit out there that is more challenging but then again you'll have a lot to think about (I bet you'll be thinking easy to fly? what are those jerks on PPRuNe on about?).
As Evo says when you get on to cross countries and nav exs you'll find it a useful mount.
After you qualify you find the bigger engine PA28s pretty handy tourers - true 4 seaters (well provided the seats aren't filled with lardy prop forward types and you don't want to go a long way - but lets face it without one of the those bed pan jobbies sombody's gonna want to stop after 2 1/2 - 3 hours anyway with 2 you can top the tanks (well if Mrs R can be pursaded to leave the kitchen sink behind) and really cover the ground. Although much derided as characterless span cans
This being where AR hijacks the thread (sorry):
Incidentally, the Rimmer mounts of choice (well not of choice – see the lottery win thread) are the Archer and the Arrer of the a/c I fly currently the two Archers are Mk2s with the Warrior wing while the Arrow is a Mk2 with a Hershey bar wing. Now here's the thing the Arrow presumably because of the higher wing loading is more 'solid' in its handling - and again probably because of the higher wing loading drops like a brick in landing configuration and power at idle compared with the Archer. Now my question is anybody got experience of both Hershey bar Arrers and Warrior wing (Mk3s and IVs) and care to comment on noticeable differences between the models. I only ask because one of the guys down at EGKA who's flown Traumahawks a lot (also Hershey bar wing) reckons they too do a good brick impression with power at idle.