Shimano vs Pearl Izumi sizing

[brucehappy]

I'm looking at buying a pair of used Shimano RX8 (SH-RX800) shoes on ebay, and I'm wondering if anyone's got a pair of those shoes AND a pair of Pearl Izumi SPD shoes and can speak to how close the sizing is between brands (this is probably a long shot).

I've got a pair of PI X-Road Fuel III in 44, but I've never owned a pair of Shimano shoes so don't know how they compare (I know they are the same company, but still). The sizing chart Shimano offers includes a CM scale, and to use it, I presume I should be measuring the inside of the shoe I already have, as opposed to my foot, heel to toe. If I do that, then it looks like it falls between 44 and 45.

And note, I'm asking here since I do not want to find a LBS with one in stock for me to try on only to go buy elsewhere used.

Thanks in advance!

[giordana93]

shimano run pretty true to size, so if you normally take a 44 in other brands, you're likely a 44. the measurement is of your foot, not shoe.

[brucehappy]

Thanks very much @giordana93. Unless anyone else has info about the RX8 specifically not being true to size, I'll be on the prowl for a 44.

[520arachnid]

They run about the same imo

[srode1]

I have 4 sets of Shimano shoes including the RX8s in size 44 and they all feel like they fit the same to me.