Some speed easel are made undersized, to allow you to 'pin in' d/w or s/w fibre based paper, which often tend to curl towards the emulsion side.
You may be happier in the long run with either A: a four bladed easel. (No, they usually are not cheap, but can be set to 1/8" borders), or the cheapo B route I outline below
If you are sticking with RC, a flat easel with two edges lets you do 'bled/bleed' printing ( I have heard the term used both ways).
I use a cheapo 9x12 two bladed easel for my bled RC printing efforts, with the adjustable blades removed.
I draw the 5x7, and 8x10 paper sizes on the easel baseboard with a sharpie mearker to aid in composition, since there are no blades to guide you.