For reference: a quick check on Fowler's website of all hoses, totals up at £188 + vat + postage - about £230 all in.
Current SFS Performance price list has Yamaha FZ1 and R1 kits for around £150 + vat, and most other Yamaha kits much cheaper (FZ6 is £136). In fact they've hardly any bike kits priced over £150. Obviously silicone hoses should be much better than stock and last way longer. So basically, any price under £200 should be pretty attractive. At the £150 mark they'll be a no-brainer.
There's a question mark on clips - ideally we'd want fresh clips to fit at same time. Be nice to get a good deal on whole she-bang - hoses & clips.