not all clubman bars are created equal. width, rise, and drop all vary depending on brand. the original design of clubmans was to fit small euro twins and singles in the 50's and 60's and to meet spec in a racing class. from the word go they were kind of a cheat. on SOHC4s you need to be mindful of clubman rash - these are dents in the tank because of an improperly installed clubman bar. I see it a lot on F bikes - it is a sign of pure hackery and will only tell people you have no idea what you are doing with bikes.
remember the bars, seat, and pegs are all one system connected by the rider. a change to one affects all and usually requires more radical changes the lower you go.
to me they don't even look cool anymore, they just look like a compromise. If you don't have the foot peg position to match, i.e. rearsets, then you are just wasting your time. even if it isn't short term "painful" (like you have "gotten used to it") you aren't doing your back or wrists any long term favors.
provided the ones you bought will even fit a Japanese fat four cylinder, you may not be happy with them. Plus I don't know how committed you are to changing your riding position for a set of $15 bars. most people aren't. Honestly, if you aren't going to spend for the clip-on, rearset, seat setup tayloring it specifically to you then why bother? the only thing you are going to get out of clubmans is heavier steering (which you may think feels "more precise" but that has more to do with the width of the bars than how low they are).
a superbike bar gets it name from ama superbike racing. Like the clubman it was designed to "cheat" a rule in a specific racing class. Racers of big jap fours in the 70's and 80's needed a wide bar to really hustle those big heavy suckers around the track and something that offered more leverage with the stock seat (usually shaved) and modified peg position. The upside is that they also work well with the stock pegs and seat. sometimes a smaller super low bar isn't the gateway to performance - sometimes just more leverage is.