Both are exceptional bows. I own and shoot both. Just got the call today that my longbow limbs are ready for my Bob Lee recurve. Paul Brunner recommended the Bob Lee to me years ago when he was running Screaming Eagle. He also mentioned the Silvertip and said that the Lee was a great bow but the Silvertip (at that time) offered more options to customize (exotic woods, etc). Bob Lee is turning out some very sharp looking bows these days with many custom options with wood, overlays, etc.
Can't go wrong with either one.