As with all these "what should I buy?" threads, it comes down to what you want to do with the boat.
I have just sold a Cobra 7.5 and thought it was fantastic. It did exactly what we wanted - comfortable, fast and great to lounge around and picnic on when you got to where you were going. However, it was not the greatest rough weather boat coz it would slam into head seas a bit - not too bad, but a bit - but that was not a major concern of ours as it would handle anything we would go out in with ease. Friends of ours have a Vipermax and that is a great rough weather boat. They go out jumping off waves and that sort of stuff - the boat takes it beautifully - but if we went out together they would jump on to ours once we got to our destination because the Cobra is so much more social and comfortable to sit around on. Try having a comfortable picnic on jockey seats!
You pays your money and takes your choice - you still have to pee in a bucket on either though which is why we are swapping ours!
Can't comment on the Stingher - we looked at one and didn't like the look compared to the Cobra. I'm not sure whether "Italian design flair" looks right on a cold wet British summers day!
On engines - don't be fooled into 4-strokes. They are heavy, expensive, over-complicated monstosities that cost a fortune to service every year. They are another media smokescreen. Buy an Evinrude ETEC - fantastic!
You can't put your foot down if you haven't got a leg to stand on.