i am also 5'9" and have always ridden a 21.5" road bike since i was 14/15 years old.
i recently got a 25" raleigh competition 531 and i find the extra size no problem at all (except when its really windy, i'd rather be on my lower bike!)
it took me a few days to get used to getting on/off it, but now it doesnt even cross my mind. its probably done me good getting used to stretch over it further!
that is a lovely RRS by the way
88 Raleigh Kelloggs Pro Tour (Reynolds 501) - owned from new
90 Raleigh Eclipse (Reynolds 501)
82 Raleigh Competition (Reynolds 531) SOLD
87 Raleigh Centenary (Ltd Edition no. 72 of 100, with gold plated Reynolds 531C frame)
88 Raleigh Esprit (owned from new)
90's Raleigh Ascender MTB (owned from new)