Bose are ok...they are not exceptional, they are not crap...unlike sony speakers which are just tinny and have no drive. So out of those two, get the Bose speakers.
However, tbh, don't bother upgrading the sound system in your car, it is a waste of money and time. All the sound goes out the window, you can never get good acoustics because of the very shape of the car, a system that has 10k Watts of power is not necessarily good, just not needed and probs sound crap as the metal in the car will resonate. Put simply, i would spend your hard earned money on a decent HiFi to keep at home and really enjoy, this will sound ten times better than the best stereo system you can put in a car.
I would recommend Kef or Linn Kelidih Speakers, with Marantz Amps, Denon sources and a Yamaha EQ and crossover. Unfortunately this setup will cost in the region of £7k, but trust me its well worth it!
However, if you cannot get it all in one go, start with your sources (CD, Tape, MD, Decks) as this is the key to getting good sound. You can have the best amps and speakers in the world, if you put a crap source through them they will sound crap. Denon equipment is really good, however you need to test out alot of stuff!
This is the order you should get your equipment:-
Sources --> (Equalizer/Crossovers -->) Amps --> Speakers
Brackets denote optional, but will give better sound.
If you are however persistant to get a car stereo, JBL and JL Audio do the best budget speakers, there are many other companies that do premium speakers which will give you better quality, but still not the same as if you were to buy a proper stereo for home. If you are looking for high quality (i.e. you are like me and an audiophile, titanium and ceramics are good things to look for in speakers! Oh and obviously, the more powerful the magnet, the better! If they are Alnico...real good!)
Oh btw...if you have not updated your head unit, update this before your speakers, remember your source is the most important part of the whole system.
Hope this gives you some ideas, sorry for the length!
Graham