Hi Jim,
I just finished my Fran Twister last week. Haven't been flying yet, field is covered with snow. I didn't try the brass inserts but may on my next build. Everything went pretty smooth once Sig sent me a new fuselage, the first one had a pretty bad bend in it. On another note i'm using an OS 35FP. I'm not hte most smartest guy on these boards but the LA46 may be a little too much engine. The Twister is not the biggest profile out there and they don't come out too heavy. I used the 35 on a Dare profile Smoothie last year, it is about the same size as the twister and it was plenty of engine. I have a LA46 but I'm saving it for my next build which will be a pathfinder or Cardinal. Thes two have a lot bigger wing and fuselage. I'm not trying to change your mind, but I would ask someone with more knowledge than me about your choice. An overpowered ship can be a pain to slow down.
good luck,
Rich