Ok so on both points
1) Mobile website vs responsive/adaptive website - Responsive / Adaptive websites hands down
pros:
Easy to maintain
Content is the same on mobile as it is on desktop
Richer user experience
Its a full blown site with all the functionality, just for a smaller resolution
cons:
bandwidth utilization
loading times due to bandwidth issues
To each of the cons, here are my thoughts
bandwidth is getting cheaper day by day
most users are on WIFI at work or home anyway
Loading times wont matter much because of better bandwidth, plus cell phones are getting more processing power
2) Responsive vs Adaptive
I prefer responsive because it takes up the desired width on the screen irrespective of the exact breakpoint
