In an exclusive pre-Chinese Grand Prix interview, Christian Horner has told that rather than irking him, he in actuality takes heart and encouragement from Red Bull Racing's F1 2010 rivals querying the legality of the Adrian Newey-designed, Renault-powered RB6 - seeing it as proof that the energy drinks-backed outfit has its adversaries frightened about its pace.

Much has been reported of late about several teams' conviction that the RB6 is only so fast because it employs a controversial ride-height control function that allows it to qualify on a light fuel load and then allows it sufficient ground clearance when the tank is subsequently filled to the brim on race day - an innovation that governing body the FIA has declared as illegal.

Red Bull team principal Horner has repeatedly insisted that there is no such system in-place - and that were any team to begin using one, RBR would be amongst the first to protest it. Rather, he puts the ultra-competitive nature of the car that has sat on pole position for every grand prix this season to-date down to the hard work of the design and development team - and the widely-renowned genius of the only man in the sport to have won more grands prix than the legendary Michael Schumacher.

"I think it's interesting," the Englishman reflected. "There are no ride-height control systems on our car. One has to take it as a compliment - it's a sign that a car is genuinely quick when others start questioning its legality. Inevitably, it's not down to just one thing. The guys under Adrian's leadership have done a great job in Milton Keynes of designing and producing a car that has built upon the very positive characteristics of the RB5 from last year.

"We have a very talented group of people in the team all working collectively; they have made some good gains and they are continuing to make good gains, because there is a hard ongoing development battle now. We need to keep producing updates in a timely fashion, and our aim is to try to put more performance on the car at every grand prix. That was what we managed to do last year, when we arguably had the fastest car following the introduction of the double-diffuser."

Red Bull, of course, looks likely to be embroiled in a fierce four-way scrap for supremacy with McLaren-Mercedes, Ferrari and Mercedes Grand Prix this year - and whilst he makes it clear that the last thing the squad will ever do is to underestimate any of its esteemed competitors, Horner does concede that he derives a real satisfaction from having come in with an unheralded independent operation and taken the fight to F1's traditional 'grandees' in barely a handful of years. Now, he acknowledges, the task is to see the job through - as he eschews any notions that his own team is in the strongest position of any of the quartet to scoop the laurels.

"I think all four teams are potential race-winners," the 36-year-old underlined. "They are phenomenal teams, and sometimes you have to take a reality check because of the big names you are up against. McLaren and Ferrari have historically been the two dominant teams in F1 over the last 25 years, and Mercedes are last year's world champions. They are all very strong, established teams, and Red Bull Racing has come a long, long way in a very short period of time. It's great to be up there rubbing shoulders with them.

"It's going to be about who does the best job over the course of the season. We are just going to stay focussed on the job we are doing. It's for other people to gauge whether we are the favourites or not - that's not a tag that we are interested in. We are just interested in putting more performance on the car between now and the end of the season. Only time will tell if that is good enough to win."

One driver whose comparative underperformance thus far in 2010 has only served to further play into RBR's hands, of course, is seven-time F1 World Champion returnee Schumacher - but Horner warns that it would be foolish to write the record-breaking German off too soon, and also offered his thoughts on the newcomers' travails, having cautioned pre-season that Lotus, Virgin and Hispania (HRT) should not be judged too early.

"I think if you watch the whole of a grand prix weekend, you can see signs that he is progressing in terms of bringing himself back up-to-speed," he opined of 'Schumi'. "Up until qualifying in Malaysia, he was looking very, very quick. I think he is just starting to find his feet. He is a very competitive animal, and I'm sure once the car is in a position to give him what he wants, he will be competitive. Thankfully for us, he's not quite there yet!

"I think [the new teams' plight] just proves how difficult F1 is - you can't simply turn up and be competitive. The first result is even being on the grid. Lotus seem to be trying to do the job properly, Virgin have had issues and for HRT it's obviously still very early days. It all just goes to further highlight how hard F1 is as a category."