CapnCop... One 355N is more "out of service" than the others and will require more-than-normal number of parts to encourage it skyward once more.
Of interest from the CAA's G-INFO website and working on approx 1000 hrs pa average per airframe
G-SEPA TT11280 at 31/12/2004 (so approx 13700 now?)
G-SEPB TT11380 at 31/12/2006 (11800 now?)
G-SEPC TT 9124 at 31/12/2004 (11500 now?)
So, very approx figures, these three have about 37,000 hours between them. I can just see the advert now "Genuine one owner from new......"