yeah, nice build
Some consideration:
1) you could drop 1 rogue level and take fighter 11 for epic specialization (damage vs evasion)
2) could also swap 1 ab for more skill points, more sneak, epic spec and uncanny dodge by taking 3 rogue levels (start rogue for more skillppints), 7 fighter levels and 10 BG at level 20
You'll then end up with 4 rogue levels, 8 fighter levels and 28 BG levels at level 40. Rogue gives uncanny dodge, so this is viable for dexers and fighter 8 means epic weapon specialization which is handy for low-strength dexers