Well typically you're going to fill it up with clothes and other things to keep everything packed nicely and padded in transport.
My bag usually weighs about 20 kg fully packed with a full set of gear and some clothes. You wouldn't be going past 23 kg in a lot of situations because otherwise airlines hit you with overweight fees.
Honestly the wheel thing is something people constantly regret when they cheap out on a board bag, but it's up to you if you're happy to put in the extra carry every time you travel. Just be aware that board bags can be very awkward to carry because they're quite long.
Personally I think the small extra amount of money for wheels on a bag you're going to use for a lifetime is easily worth the money.