Valentino Rossi and Marc Marquez may not agree on much at the moment but they both used the same phrase to describe the new for 2016 single ECU system.

The former champions, embroiled in a bitter war of words for the past two rounds, got their first taste of the control electronics - alongside further tests with Michelin tyres - at Valencia on Tuesday.

First to speak was Rossi, who set the 12th best lap time, 0.850s behind fastest man Marquez:

"I tried the new electronic for next year and it will be a big problem - I mean it is like we make a jump in the past. Like [our factory software] in 2008-2009."

But does it make the bike more fun to ride?

"For me no, because in the end the higher the level of the bike then the better it is for me. So like this is clear step back. At the beginning you are also a little bit angry on the bike because you think 'f**k! It don't work'

"But on the other side, it can be good for the racing. Because it will be a lot more difficult to always make the same lap time. Because the bike is more difficult to ride. So can be better for the battle during the race, can be more fun about this."

A few minutes later, over at the Repsol Honda hospitality, Marquez said:

"We started on the 2015 bike, then the 2015 bike fitted with the new software. That is where we spent the most time and still we must spend a lot of time, because looks like we did like one step back [in time] because it will be difficult to arrive at the same level as before.

"But we are working, especially on the acceleration side, traction control, torque delivery is where we must improve. The connection with the gas. Then in the last runs we tried the new [2016] engine, but honestly it was difficult to give the right feedback because still we must fix the electronic software."

Given Marquez's much-publicised struggles with the aggressive 2015 engine character, is the rough nature of the new software a concern?

"Yeah, with less electronics of course if you have an aggressive engine you will have more 'cuts' [in the power] and looks like this electronic is working a little bit slower," replied Marquez. "The 'cuts' are coming later and bigger so we must fix it well."

The Spaniard, one of many to suffer a front-end fall on the Michelin tyres today, admitted the 2016 electronics are a bigger concern than the change of tyre brand.

"For me electronics because in the end the tyres are the same for everyone," he said. "So the tyres will not be the biggest problem and I think Michelin are doing a good job. On the other side, it is only the first time we ride with the electronics and we know it takes time to set them up.

"In Turn 13 I nearly highsided one time, but I can say the new electronics are safe. They are just not very smooth and cutting too much."

The factory teams have previously been able to use their own bespoke software, but all riders must use the same ECU system - being jointly developed by Honda, Yamaha, Ducati and Dorna - next season.

Testing concludes on Wednesday evening.