I bought these to put on my Ibanez RG827 (which I also got from Thomann!!;). I have always used Ernie Ball strings on my 6 string guitars, so I got the same for the 7 string when I bought it. The string tension with these 10-56 strings is just right in standard tuning (BEADGBe).
However, I have been experimenting with alternate tunings lately, in particular open Dmadd9 with a low A (ADADFAe). There isn't a huge tension change in the first 6 strings, but the 7th string low A is a little loose with this string gauge and the tuning does waver slightly. I think I may have to up the string gauge the next time I get new strings, as these are a little light for what I want to do.
If you want to play in standard tuning these are great, but of you want to tune lower, you will need heavier strings.