I think if you can get to a Thomann store to try them in person by all means do and post your impressions here please! If you can't try them steer well clear, if the price is unbelievable there's probably a very good reason! Weighted hammer actions are complex and expensive to produce, to make a cheap one you have to cut corners somewhere.
BTW it's quite likely that particular member will post in this thread that all digital pianos are good and that a reputable company like Thomann wouldn't stock rubbish. You will find that he is the only person on this forum that holds that view, there's a reason for that too
If money is tight look at the following models, they're all good entry level instruments.
Korg Sp170 - odd method of changing voices but very nice touch and good sound. €468 at Thomann
Yamaha P95 - Good basic piano with Yamahas excellent build quality, not as high spec as the Korg and Casio but still worth considering. If you can find a P85 it should be quite a bit cheaper, it's the fore runner to the P95 and almost the same instrument. €618 at Thomann
Casio PX130 - Very popular model, good value, maybe slightly lower build quality than the others but still a decent instrument. €619 at Thomann
Kawai CL-25 - I've never tried one of these but Kawai make great pianos! I suspect it uses older sampling technology from a generation or so back when Kawai weren't noted for their sound, it should have a great action though and you can always use an external sound source (computer or module) to improve the sound. Well worth trying if you can find one - potentially the best of the bunch - €659 at Thomann