"It is amazing to have so much detail for every single thing you do through the day with the club.
"I wanted it to be like this at Biarritz because I always said it was the only way to reach the top. It frustrated me that it wasn't the case.
"It's a different view of rugby. We don't think so much about the game in France, it just happens.
"I have never spent so much time on fitness and preparation. I now know why the English clubs and the Premiership is the best in Europe.
"It will be incredibly physical against Castres and the amazing thing is their unpredictability.
"But we have done our analysis on them and hopefully we can bring our power game and execution together at the same time."
Wasps' spartan West Actonground could not be in starker contrast to Biarritz magnificent facility Parc des Sports Aguilera.
"It's quite different to Biarritz where we have a new stadium, plush changing rooms and a chic gym," Betsen said.
"When you come here and see the working conditions you know you will have to suffer to win something. When you come here you work hard every day to get better. I love this spirit."
The loving feeling seems to be mutual, with Wasps' hard-nosed coaching duo of Shaun Edwards and Ian McGeechan unusually gushing in their praise of their 63-cap France veteran.
"Serge has been a massive signing," McGeechan said. "Within the club he is very well respected, the players think he is fantastic and since he has come in and been part of the first team he has been phenomenal.
"He's the most popular player at the club," Edwards added.
Betsen will be a key figure on Sunday as he looks to negate the threat posed by Castres' former All Black No7 Chris Masoe and provide Wasps with the platform to achieve something they have failed to manage once in Europethis season - score four tries. After a desperately slow start to the season, the defending Guinness Premiership champions and two-time Heineken Cup winners are finally beginning to click.
They have won six of their last seven games in all competitions but Edwards know Sunday's game will be as tough as anything they have experienced.
"Every single player I have asked about which game was the toughest on the way to the 2007 Heineken Cup Final has said Castres away. That is including the final.
"That is no disrespect to other teams we played on the way but in terms of shear physicality and the exhaustion levels of the players, there is no doubt Castres away was the toughest game.
"There were guys nearly collapsing in the dressing room and guys saying it was tougher than some Test matches they'd played in."
Wasps, who have still to announce a single new agreement with any of their 19 out-of-contract players, despite McGeechan's protests that "things are coming along nicely", can take comfort from the superb form of their two international wingers.
Paul Sackey and Josh Lewsey were outstanding against Leinster and are sure to be marked men against Castres on Sunday.
"That is as hard as I have seen wingers run in the competition," Edwards said. "The ferocity they were hitting the line at was outstanding.
"Sackey's fend and Josh's power at the line was outstanding. There's no doubt the Leinster defence had a little bit of trouble with them.
"Sackey looked razor sharp and Josh prides himself on being a big-game player. He knows there is a Lions tour at the end of the year. I'm pretty sure he was aware he is in competition with some of those Irish lads for places."
