Non-standard bokken/ bokuto

[Cypher]

Having read of the Sasaki Kojiro Suburito on bokkenshop.com, I have been wondering about how common it is for practitioners of either iaido or kendo to practise with different bokkens other than the standard, or standard suburi. For example, the super-heavy octagonal suburi for strength building, or lighter bokken for technique. Any information would be of interest, thank you for your time.

[Kirin]

many of bokkens in that website is very uncommon, and not practical.
especially kojiro or musashi bokken. I think they just made yup their original bokken.

many people uses standard bokken for normal practice, and ittoh-ryu bokken for strength building.
but some koryu uses their orignal bokken very similar to itoh-ryu bokken.