I would swap one of these for Mithral Body, probably Epic Reflexes; it's nice, but with Imp Evasion and the extra MRR from Mithral Body, you hopefully won't need it.
BTW, unless I'm miscounting, your feat list is missing one; do you have Overwhelming Crit?
You don't make a Concentration check when using SLAs (inc. BF Recon), so it that sense they're uninterruptible. But you can still be stunned, knocked down, etc. - or simply killed - before the SLA finishes casting; and un-Quickened Recon can feel agonizingly slow when you're really getting beat on. Plus the sooner you finish repairs, the sooner you get back to the violence.