Sorry I can't answer your question. Graham Smith, a bloke from Canberra who posts often on Crazyguyonabike has a Performer bike and says it's very good.
Looking at the Performer Duet, the frame seems quite small, the Milanos come in larger sizes too. In Australia we'd probably punt for a 2013 Apollo Syncro 700 in this category - 105 and only $150 more on RRP.
The gumtree advert for the Duet says they'll post to most countries. Remarkable value is to be had in terms of sending bikes all over the world, it appears, eg Ribble will post a road bike UK to Australia for $150, which makes a 105 triple-equipped Sportive 365 a bargain!
Good luck!