" The bat has no strings, so I can just similarly use the hardness of the bat to know its "trampoline effect" (ability to generate power using the hardness of the strings)?"
Unfortunately, it's not as simple as that. For rackets made with fiberglass or carbon frames, this can definitely play a big role, but so does the type of foam, the amount of carbon and several other elements. Thus, there are often several things to consider in a padel racket and we therefore recommend that you read through this guide carefully and possibly ask in a specialist shop if you want to find out how much power a racket can generate.
"The round racket is only for beginners, as this one can't hit as hard as the oher bats"
This is a big misconception that is seen among many new players in the padel world. This misconception is mainly based on the fact that 9 out of 10 of the beginners' rackets in the market are made round, as these are usually easier to play with as a beginner. However, this does not mean that round control bats cannot be enjoyed by a more experienced or professional player. In fact, several of the good players on the World Padel Tour play with round rackets, which just underlines that the head shape does not exclude some players, but just shows the difference in playing characteristics.
" A padel racket costs the same as rackets for the other sports, so the price and quality are comparable"
Padel rackets are generally a little more expensive than tennis, squash and badminton rackets, so be prepared to pay a little more to secure a racket of similar quality. Padel rackets, however, as with the other racquet sports, price and quality don't always go together, but it often goes that way, which is why you can't expect to get top rackets for the same price as beginner rackets. However, we definitely recommend that you both test yourself and talk to professionals when it comes to buying a new racket - this is often a bit of a stretch for most people and you therefore want to be sure that you find the racket that best suits your own abilities on the court.