Price difference between clubs
The 2 clubs I do most are Grimberg and Arabella. Both have 20 euro happy hour entry from 10 to 13 and 17 to 22.
From 13 to 17 its 30 euro. This is liable to change anytime.
The cheapest session in Grimberg is 30 for 20 minutes, and in Arabella it's 40 for 30 minutes, also 40 for 30 in Grimberg, and for both clubs -50 for 40 minutes and 80 for an hour.
Grimberg seems busier at the moment because many local guys still opt for the 30 euro session instead of paying 40 in Arabella.
I've spoken to some veterans who believe the 20 min session is close to 20 minutes, while the 30 min session is more like 20 or 25 minutes.
I usually opt for 30 min sessions although it's Nice to be able to quit under 20 minutes if it's going crap in Grimberg.
I always find hour sessions a bit of a Rip off, because girls often call time around 45 or 50 minutes. A 40 min session often runs to close to 40 minutes and it's 30 euro cheaper for a very similar experience to an hour session. That's my experience anyway.
The bigger clubs in Frankfurt may have gone sky high with 150 Euro half hour etc but the budget experience is still alive in Rtcs in NRW.
Grimberg now 40 euro per 30 min session
I just read on local forums, that 30 euro session is no more in Grimberg and that 40 euro is now the lowest price for a session. I guess all rtcs have the same pricing now.