Sultan. I think the economics is another debate. Bell's most recent design,the Valor , with horizontal engines is a step towards reducing complexity and acceptability in the civil market but the tilt rotor still seems to be the Concorde as against the more utility X3. I guess it will be horses for courses as the tilt rotor will have undoubted speed and range advantages where those are needed but at a cost.
Interesting to compare with what Westland did with the Berp blade that made the Lynx speed record possible.
Instead of developing it to routinely go faster they used the technology more to increase lift and payload,hence on the AW101 they achieved the required performance with five blades,rather than the six that would otherwise have been required without Berp technology.