I think the Red Bull is quick, that's not it's problem though - the problem is that it's not reliable, and to be quick you need to turn everything up, the revs, power train, engine et al all need to be pushed to the limit, and that's where they have a problem because all those things get too hot even when the car ISN'T at the limit.
Aerodynamically RB have always done well and they have the "God of Aero" still at the helm so they're bound to be decent when the issues with the car are sorted out... but there is an element of engine power that will be more important than ever this year and I have a feeling that the Mercedes, as well as being more reliable has more performance too.
Unfortunately for RB, and fortunately for a lot of us
D) they are running out of time to find a solution, or compromise if you will, where they can extract maximum performance and maximum reliability at the same time.
Factor in that after Sunday (I think it's Sunday or very shortly after) Renault and Red Bull will not be able to enhance the performance of the Engine until 2015, so a whole season of running on what they managed to achive from testing.
The problem is they're so incredibly on the backfoot now with reliability and making sure the car gets to the chequered flag that they aren't going to be able to master both reliability and performance... where as Mclaren, Mercedes, Ferrari and the other Merc powered FI and Williams etc. have got a monumental amount of data to trawl through and numbers to crunch, so much so that they will be doing Qualifying sims on the last two days and eeking out every last drop of performance from the power units and engines.
If they manage to iron the cooling problems out I think it will be a quick car, whether it will be as quick as the Mercedes or Mclaren will be another story but one thing's for sure right now... Red Bull R B 10.