Weighing up between 3 bikes and after some opinions...

Avanti Cadent 2.0

Argon 18 Krypton

Avanti Quantum 2.0

Similar pricing so interested in the pro's and con's

What do you want to do with it? And at what level?

Argon Who??

Cadent Vs Quantum

what kind of riding are you doing?

what are your goals for the next 12, 18 and 24 months

I'd also look at Specialized Roubaix V/s Tarmac, spec not quite as nice for the $$, but they always ride well IMHO

Specialized have a reputation for nice ride quality, Important if you are doing miles.

They are pricey compared to other brands though so you will get less bling for your $$$$

Which one do you like the look of most?

Seriously, they're all great bikes so it's a matter of nuance as to which one you choose. My proposal is that you take each option for a test ride if you can, then decide which one you like the look of most.

What do I want to do... mainly ride for fitness but also look at the odd race like the R4 or Rotorua Flyer etc. Fairly new to the game. As bikes aren't cheap I figure I'm best to get a pretty good bike in the first place so I'm not constantly upgrading gear or having to change bikes in the not so distant future. From my other sport I've found it's cheaper in the long run to get the good stuff at the start.
I like the specialized stuff too... but a fair bit more expensive. I have set myself a limit !

So far I've ridden the Krypton and the Cadent so far. The Cadent being alot harsher ride. I expect the Quantum to be harsher again... which I'd accept if it was noticably faster/more responsive. So currently I'm tending towards the Argon. I believe the carbon bars absorb alot !!!

Looks wise I like the Avanti's curved top tube and tube shapes (looks like alot of specialized influence) but quite like the Argon 18 brand in being a bit more unique. So I guess it comes down to which is the best bike...