These are the ones that I bought - 25mm lift - http://www.ebay.co.uk/itm/Yamaha-Fazer-F...0319010605
I notice that there is a new German eBay seller on the block that is doing them at 20mm / 35mm / 50mm I'm now considering getting the 50mm ones as I'll have better control over the ride height with my shock rather than just having to have it on maximum - http://www.ebay.co.uk/itm/Jack-up-Kit-Ya...1787930549
You have a point about luggage but personally I'd be using the centre stand if I had the bike loaded up regardless.
If you're still on the OEM shock then another advantage of a jack up kit is that it slightly alters the suspension geometry making the shock feel firmer.
I notice that there is a new German eBay seller on the block that is doing them at 20mm / 35mm / 50mm I'm now considering getting the 50mm ones as I'll have better control over the ride height with my shock rather than just having to have it on maximum - http://www.ebay.co.uk/itm/Jack-up-Kit-Ya...1787930549
You have a point about luggage but personally I'd be using the centre stand if I had the bike loaded up regardless.
If you're still on the OEM shock then another advantage of a jack up kit is that it slightly alters the suspension geometry making the shock feel firmer.