I've got a set of the Samson fids and I hardly ever use them. Granted, I'm not splicing covered line very often - mostly 12 strand Dyneema / Amsteel and the like. I use a simple splicing needle and it does everything I need to do.

For the model sailboats, I took a moderately sized sewing needle and blunted and polished the end. It works great for splicing 1/32" spectra line for the r/c boat. There's not one single knot on my whole US1M!