I have a PX-5S on order; it should arrive within the next week. I think that it's one of the instruments with the best quality/price ratio on the market today, and it weighs just 24.5 lbs or 11 kg (a Tyros 4 weighs 14.5 kg).
Aside from the sounds, I intend to use it as a master keyboard, to control both the Kronos 61 and the Roland BK-7m. Being just 28 cm deep it should fit nicely under the Kronos and still be perfectly usable and readable.
Can't wait to try it.
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Korg Kronos 61 and PA3X-Pro76, Roland G-70, BK7-m and Integra 7, Casio PX-5S, Fender Stratocaster with Fralin pickups, Fender Stratocaster with Kinman pickups, vintage Gibson SG standard.