Colour mode II Adobe RGB and on-line printing labs

I know the answer to this is probably "try it and see", but I was wondering what results I should expect if I send jpg files to an on-line photolab (such as photobox.co.uk) that have been taken in Adobe RGB colourspace ?
I can't find any mention on their website, and I'm wondering if it's something I should only be using if I intend to print at home (which would be a bind, as my photo printer is a bit on the clunky side, and I don't really want to invest in a new one, as I print all my 'keeper' shots on-line)
Or am I worrying too much ?
I can't find any mention on their website, and I'm wondering if it's something I should only be using if I intend to print at home (which would be a bind, as my photo printer is a bit on the clunky side, and I don't really want to invest in a new one, as I print all my 'keeper' shots on-line)
Or am I worrying too much ?